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DAVID MALAN: So why don't we
go ahead and begin our 1:00

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PM to 2:00 PM Eastern session--

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an overview of the classes that you
can teach before or after CS50AP.

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This, like a lot of CS50, will be a bit
of a fire hose-- a lot of information.

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But it's really just meant to give you
a taste of what is available to you

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optionally.

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Indeed, over the past
few years, though we

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began with just CS50 the
course, which composes

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much of our discussion
in the past few days,

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thanks to Brian and Colton
and other colleagues of ours,

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have we begun really building
out a curriculum of sorts that's

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particularly well-suited for high
school and/or middle school students,

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so that teacher is
teaching CS50AP don't just

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have one curriculum at their disposal.

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But they have more runway
for their students.

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So students might take
one class before CS50AP,

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one or more classes after
CS50AP, or just CS50AP,

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or one of these other
classes themselves.

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It really is up to you how
you might like to assemble

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any of these building blocks.

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So we thought we'd give you a whirlwind
tour of six other courses, one of which

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you've seen already, and three of
which are related to one another.

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So it's not quite as
much as it might seem.

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Brian, you know.

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Allow us to have our colleague
Colton say a formal hello,

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so you know whom to expect
in a few minutes, too.

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COLTON OGDEN: Hi.

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Nice to see everybody here.

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Hope you're all staying safe.

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DAVID MALAN: Colton will be
introducing in just a bit

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our game development class,
which is particularly

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well-suited for a lot of high
school students' interests.

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So here on the screen,
you should see next to me

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the list of six other courses that
are currently in our curriculum.

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All of them have a single or one or
two characters that describe them.

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CS50B is a course for computer
science for business professionals.

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CS50L is CS50 for lawyers.

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CS50T is understanding technology.

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And then we have three
follow-on classes, CS50AI,

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which is an introduction to AI with
Python; CS50G, taught by Colton,

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an introduction to game
development; and CS50W,

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like CS50AI, taught by Brian, Web
Programming with Python and JavaScript.

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And I think if of any interest to
you in teaching these classes, be it

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this coming year or down
the road, hands down,

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I think the best
preparation for doing so is

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to simply take the courses themselves.

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They're freely available
as OpenCourseWare.

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We'll provide all of
the URLs as we go here.

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But they're also centrally located,
if you would like, on edx.org, where

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you can sign up for
free for audit status

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and follow along at
your own pace, if you

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might want to prepare over
the summer or some future year

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for any of these curricula.

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And indeed, that's much like
our own teaching fellows

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become teaching fellows because they
have quite simply taken successfully

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any of these classes.

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To help give you a mental model
for how everything fits together,

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if you think of CS50 itself or
CS50X, the OpenCourseWare version

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of the class, as the
backbone or the main class

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that students have
long taken at Harvard,

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these other courses now
fit into that pipeline

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either as predecessor
courses or follow-on courses.

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So a possible model would be for
a student to take CS50b or L or T,

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and then CS50X, and then
to take CS50AI or G or W

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or even multiple combinations thereof.

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The first three courses
on the left, B, L, T,

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are essentially mutually exclusive.

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We'll see that there are
differences among them,

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so they don't need to be
taken one or the other.

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The three follow-on courses
can be taken in their entirety.

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So you could imagine, for
instance, at the high school

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level, perhaps a student starts
out freshman year with CS50T.

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Maybe sophomore year, spends
time on CS50X or really CS50AP.

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And then maybe junior
and/or senior year,

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has an opportunity to
take something like the AI

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class, the games class,
for the web class.

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Of course, two of these
we're now well familiar with.

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CS50T plus CS50X compose what
we've been calling CS50AP.

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So please interject at any
point if you have any questions.

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And if I miss a hand, Brian
or Colton, please do just

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chime in and call my attention.

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But why don't we dive
in first, just more

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formally, to CS50T,
which we've been taking

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for granted as just part
of CS50AP's curriculum.

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But again, factoring
that out and maybe having

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less comfortable or younger students
simply start with that piece,

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as opposed to diving into CS50AP
itself, is one viable option.

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So here comes the whirlwind tour.

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The syllabus of this class
is essentially divided

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into these six large topics.

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The goal of this class ultimately is
to provide students and of any age

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with really an understanding
of the technology

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that they see and hear about every
day, but don't necessarily understand.

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And we break the course down
into these six components.

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And let me give you a quick
tour of each of those.

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So on the hardware front, we
start, not unlike CS50 itself,

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with a look at binary,
and more generally,

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representation of information.

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But we focus a bit more on
hardware than we do in CS50 itself,

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looking more at things like
CPUs, the brains of the computer;

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hard drives, and how data is
actually stored underneath the hood;

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and even talking about
peripherals and connectors,

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the plugs that you see on
the back of the computer.

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Colton might remember this
throwback from a few years ago

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when we filmed this.

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The course also, albeit on
video, has this lab component

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where we take things apart.

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We show students on camera
pieces inside of a computer.

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And so what's especially
fun about CS50T,

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really, in isolation, if it were taken
or taught as a course unto itself,

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is if you have access to an
old computer, a PC or a Mac,

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that you can take apart,
it's actually a lot of fun

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to enable students to play more hands-on
with what's inside the computer,

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or conversely, to have them build up
a computer based on those same parts.

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We then focus in CS50T on
the internet and what it is.

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And we talk about things that many
students will take for granted.

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If they're fortunate to have
internet access at home,

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we contextualize what that cable modem
is from Comcast or any other provider

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and what all of those
wires actually do and mean.

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We show them on their Mac
or PC incarnations of how

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they're connected to the internet.

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So we talk about IP, IP
addresses, and DNS, and DHCP.

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And if you yourself aren't
familiar with that alphabet soup,

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that's totally fine.

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Again, taking the course is
perhaps the best preparation.

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And here is just a
similar view on Windows.

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And then, again, we keep
this in context with which

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students are familiar-- talking
about home networks that

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might have WiFi, that might have
wired devices, that might have phones

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or laptops or television
set-top boxes, and try

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to help students understand
the technology they see

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and/or use every day.

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We spend time, too, on
multimedia in this class.

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And we introduce
students to audio, video,

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and other forms of multimedia as well.

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And we give them a sense
of how, for instance,

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music might be synthesized, talking
about formats like Mitty, which,

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if unfamiliar, is a way of
encoding music digitally,

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so you can interact
with it with a computer.

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We talk about how
images are represented.

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Here's a 1-bit image
of a smiley face using

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just a single bit for black or white.

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We talk about image compression.

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So given an image like
this, let me actually

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ask the group, what might
the opportunity here be

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to compress an image like this if
it's stored in a digital file format?

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How might you go about compressing
this apple that you see on the screen

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here against this blue backdrop?

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Any ideas or intuition for
where the opportunity is?

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Brett?

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AUDIENCE: Yes, you could condense
and consolidate the colors.

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DAVID MALAN: Consolidate the colors?

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Yeah.

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AUDIENCE: So like all
the same blue color

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could be combined and just repeated.

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DAVID MALAN: Yeah, exactly.

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There's a lot of redundancy here.

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There seems to be some
common red, some common blue.

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So you could effectively
store that same image

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by factoring out a lot
of the common blue.

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And instead of saying the digital
equivalent of blue, blue, blue, blue,

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blue, blue, blue, blue, blue,
blue, blue, blue, and so forth,

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you could just say blue
10 times, blue 10 times.

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And just like it sounds faster, it would
similarly take less space in memory.

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Here's a clip from,
for instance, a video.

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And you have a bumblebee
on top of some flowers.

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And you can see that the flowers are
not moving, but the bumblebee is.

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And so here might be
an opportunity to get

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students thinking about
how you can save space

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by not repeating yourself as much.

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And maybe you could in a video file
format do something similar in spirit,

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but only track the
movements of the bumblebee.

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And don't worry about redundantly
storing those flowers because, again,

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they appear again and again stationary.

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Of course, it's quite
common in TV and movies

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to see ridiculous scenes like this.

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This is taken from like
CSI something or other.

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And of course, the
police or investigators

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are able to zoom in on that
glint in the person's eye

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and figure out who the suspect is.

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We point out to students
that they're just

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going to see generally a blurry mess.

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And if you can see this on my
screen, albeit a bit small,

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there is really little identifying
information of who the bad guy is,

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at least from that frame in the show.

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So we talk, too, in this class
about security and passwords.

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If you see any of your own passwords on
this list, you're part of the lecture

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now because these are the top 10
most common passwords as of a year

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or so ago.

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They're not particularly secure.

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And so we talk to students
about why they're not secure

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and how they might use things
like two-factor authentication

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or other techniques to keep them secure,
whether it's with their accounts,

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or whether it's in WiFi.

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And we also talk about issues
of privacy, for instance,

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by way of cookies.

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You've probably heard
that cookies somehow can

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be used to track you on the internet.

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We help students understand
technically what that means

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and why they're not all bad and
actually do solve technical problems.

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And then, toward the end
of the semester in CS50T,

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we introduce students to a
little bit of web development.

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And we start with HTTP, the protocol
that moves the data back and forth.

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But we also introduce them
hands-on to HTML and CSS.

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And we help them understand, too,
really as a stepping stone to something

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more like CS50 itself, that
there's ways of representing

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this information in different ways.

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Just like you have a family tree
where you might have these nodes,

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and a graph with edges and
circles or squares or the like,

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we can see something
like HTML code and start

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to think about it in
different ways, setting

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the stage for more sophisticated
discussions in a higher-level class.

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And then lastly, we focus on
programming with the students.

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And we introduce them to pseudocode and
searching the phone book, for instance,

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algorithmically.

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But we spend a good
amount of time on Scratch.

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And that is their only language in
this course with which they experiment.

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But they have an opportunity
to apply those same ideas.

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So if you're curious--

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and again, these slides
are on the website--

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you're welcome to go to this URL if
you'd like to see a sample assessment.

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I'll go ahead and paste
this into the chat window.

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Actually, let me add the HTTP.

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That's a sample assessment, but there
are other assignments week to week

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throughout the course, not just
this end-of-course assessment.

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But that'll give you a sense
of the summative questions

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that we tend to ask of students.

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And they're similar in spirit
to CS50's own in that they're

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meant to be short answers or the like.

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Before I give you a
whirlwind tour of CS50B,

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[? Hani, ?] any questions or comments?

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AUDIENCE: I'm sorry.

235
00:11:01,900 --> 00:11:04,403
This was back to the image compression.

236
00:11:04,403 --> 00:11:05,320
DAVID MALAN: Oh, sure.

237
00:11:05,320 --> 00:11:08,650
AUDIENCE: Of course, if
you save the difference

238
00:11:08,650 --> 00:11:14,148
between the pixels instead of the pixels
themselves then you can save a lot.

239
00:11:14,148 --> 00:11:15,190
DAVID MALAN: Yes, indeed.

240
00:11:15,190 --> 00:11:17,898
So opportunities to talk about
different forms of representation,

241
00:11:17,898 --> 00:11:19,900
too, of the format itself.

242
00:11:19,900 --> 00:11:22,310
So CS50B, for business.

243
00:11:22,310 --> 00:11:25,420
So this course has a lot of
overlap with the course's content,

244
00:11:25,420 --> 00:11:27,262
but the target audience
is a bit different,

245
00:11:27,262 --> 00:11:28,720
and the mindset is a bit different.

246
00:11:28,720 --> 00:11:31,510
So generally speaking, this course
is taught to older students,

247
00:11:31,510 --> 00:11:34,000
be they adults or students
at Harvard's Business School.

248
00:11:34,000 --> 00:11:37,150
But the goal there is not to just
understand technologies that we see

249
00:11:37,150 --> 00:11:41,380
and use every day in a consumer
sense, but to understand technologies

250
00:11:41,380 --> 00:11:44,682
on the basis of which you
might make this decision.

251
00:11:44,682 --> 00:11:46,390
So if you happen to
be running a company,

252
00:11:46,390 --> 00:11:49,990
or you're the CTO or the CEO
or a manager or someone that

253
00:11:49,990 --> 00:11:54,010
works with technical people, but isn't
necessarily as technical themselves,

254
00:11:54,010 --> 00:11:56,260
what do you need to know
about technology in order

255
00:11:56,260 --> 00:11:59,710
to just get real work done and
hold your own in conversations

256
00:11:59,710 --> 00:12:00,850
with more technical people?

257
00:12:00,850 --> 00:12:04,700
So as such, it can be applied to
younger audiences, certainly, as well.

258
00:12:04,700 --> 00:12:07,390
So the six categories into
which this course is structured

259
00:12:07,390 --> 00:12:10,240
are a little similar in
spirit, but these six here.

260
00:12:10,240 --> 00:12:12,400
And let me give you a
quick tour of those.

261
00:12:12,400 --> 00:12:15,790
So we begin with computational
thinking, not unlike CS50 itself.

262
00:12:15,790 --> 00:12:18,490
And we help students think
about how you take inputs,

263
00:12:18,490 --> 00:12:21,100
and your goal is to get
outputs, and in between there

264
00:12:21,100 --> 00:12:22,732
are these things called algorithms.

265
00:12:22,732 --> 00:12:24,440
But in the business
version of the class,

266
00:12:24,440 --> 00:12:27,970
we spend a bit more
time on sophistication

267
00:12:27,970 --> 00:12:32,140
of concepts like this--
so running time, and how

268
00:12:32,140 --> 00:12:34,540
you think about not just
whether or not an algorithm will

269
00:12:34,540 --> 00:12:38,370
find Mike Smith in a phone book or
solve some problem correctly, but does

270
00:12:38,370 --> 00:12:39,400
it do it well?

271
00:12:39,400 --> 00:12:41,310
Does it do it quickly and efficiently?

272
00:12:41,310 --> 00:12:45,010
So you can start to think, as a
business person might, in terms of cost,

273
00:12:45,010 --> 00:12:48,160
in terms of time or money
or the like, thereby

274
00:12:48,160 --> 00:12:51,100
having all the more building blocks
at your disposal for discussions

275
00:12:51,100 --> 00:12:52,180
of trade-offs.

276
00:12:52,180 --> 00:12:54,170
We talk about programming languages.

277
00:12:54,170 --> 00:12:57,215
So here, we give students a
sense of what's out there.

278
00:12:57,215 --> 00:12:59,590
We don't teach them any of
these languages in any detail.

279
00:12:59,590 --> 00:13:01,810
We show them simple
snippets, just so they

280
00:13:01,810 --> 00:13:04,630
can understand what features
exist in programming languages.

281
00:13:04,630 --> 00:13:06,760
But as with the technology
class, we use Scratch

282
00:13:06,760 --> 00:13:09,970
because it allows us to explore
a procedural language, as well

283
00:13:09,970 --> 00:13:13,160
as a number of topics that they'll
encounter in the real world.

284
00:13:13,160 --> 00:13:15,160
Scratch, of course,
supports things like events.

285
00:13:15,160 --> 00:13:17,680
And anytime you and I use
our phones these days,

286
00:13:17,680 --> 00:13:21,170
anytime you touch your tap or
swipe, those are all events.

287
00:13:21,170 --> 00:13:24,940
And so we help students understand
how these paradigms of programming

288
00:13:24,940 --> 00:13:27,940
map to actual technologies they use.

289
00:13:27,940 --> 00:13:30,560
We talk again, as in
T, about the internet.

290
00:13:30,560 --> 00:13:33,940
But we go into a little more
detail into the alphabet soup

291
00:13:33,940 --> 00:13:36,020
so that they understand
the kinds of jargon that

292
00:13:36,020 --> 00:13:38,530
might get thrown around
by their own engineers,

293
00:13:38,530 --> 00:13:40,840
whether they're a startup
or a larger company that

294
00:13:40,840 --> 00:13:43,900
just uses IT Infrastructure.

295
00:13:43,900 --> 00:13:45,490
We introduce them to web development.

296
00:13:45,490 --> 00:13:47,830
The goal is not to turn
them into web designers,

297
00:13:47,830 --> 00:13:52,840
but just so that they know what this
HTML and CSS and other such tools are.

298
00:13:52,840 --> 00:13:55,510
So we show them and allow
them a hands-on opportunity

299
00:13:55,510 --> 00:13:57,070
to play with HTML again.

300
00:13:57,070 --> 00:14:00,280
But we also spend a bit more time
translating Scratch to something

301
00:14:00,280 --> 00:14:02,410
like JavaScript, a
language that's commonly

302
00:14:02,410 --> 00:14:04,570
used in the context of web programming.

303
00:14:04,570 --> 00:14:08,110
So there, too, the students
of CS50B have a mental model

304
00:14:08,110 --> 00:14:10,270
of how more pieces of the puzzle--

305
00:14:10,270 --> 00:14:12,670
no pun intended-- interconnect.

306
00:14:12,670 --> 00:14:16,510
And then, quite different from CS50T,
we talk about so-called technology

307
00:14:16,510 --> 00:14:17,050
stacks--

308
00:14:17,050 --> 00:14:21,760
like how all of the various
technologies and acronyms and languages

309
00:14:21,760 --> 00:14:24,430
and protocols somehow fit together.

310
00:14:24,430 --> 00:14:28,780
And we break things down into front end,
so to speak-- the part of the interface

311
00:14:28,780 --> 00:14:29,920
that humans see.

312
00:14:29,920 --> 00:14:32,230
And we rattle off, and we
give them just some sense

313
00:14:32,230 --> 00:14:34,690
of what's out there and in
vogue these days in terms

314
00:14:34,690 --> 00:14:38,110
of libraries and frameworks
for front end technologies.

315
00:14:38,110 --> 00:14:40,330
We do the same for back
end, giving them a sense

316
00:14:40,330 --> 00:14:44,170
of what languages are in vogue, what
frameworks are in vogue-- not so

317
00:14:44,170 --> 00:14:46,150
that they know themselves
how to use them,

318
00:14:46,150 --> 00:14:48,530
but just so that they know
that, one, they're out there.

319
00:14:48,530 --> 00:14:50,305
And two, if there's
another one tomorrow,

320
00:14:50,305 --> 00:14:52,180
it's not really that
big of a deal because it

321
00:14:52,180 --> 00:14:57,130
fits into a paradigm with which
they've already had some comfort.

322
00:14:57,130 --> 00:14:58,630
We talk, too, about databases.

323
00:14:58,630 --> 00:15:00,962
And so middle tier
architectures or, depending

324
00:15:00,962 --> 00:15:02,920
on how you might want to
think about the tiers.

325
00:15:02,920 --> 00:15:07,240
And, again, some big-name products
that they might know of in Oracle,

326
00:15:07,240 --> 00:15:10,340
in MySQL, in others
as well, just so that,

327
00:15:10,340 --> 00:15:13,120
again, they've been
exposed to these things.

328
00:15:13,120 --> 00:15:14,590
Then we talk about mobile, too.

329
00:15:14,590 --> 00:15:16,465
Especially in the context
of businesses, it's

330
00:15:16,465 --> 00:15:19,700
often a decision whether to have
a website or a mobile website,

331
00:15:19,700 --> 00:15:20,575
a mobile application.

332
00:15:20,575 --> 00:15:24,050
Should it be Android or
iOS or both, and the like?

333
00:15:24,050 --> 00:15:26,560
And we help them think about
the non-trivial costs--

334
00:15:26,560 --> 00:15:30,430
again, in terms of finances
or time or humans--

335
00:15:30,430 --> 00:15:35,080
in developing solutions to all
of those various platforms.

336
00:15:35,080 --> 00:15:39,250
And we talk, too, about data itself
and how you go about structuring data.

337
00:15:39,250 --> 00:15:42,500
For instance, a spreadsheet, with which
most business types might be familiar,

338
00:15:42,500 --> 00:15:46,000
but we introduced them to SQL, which
we don't do in the technology class.

339
00:15:46,000 --> 00:15:49,510
And we introduced them to
NoSQL, again, at a high level,

340
00:15:49,510 --> 00:15:51,890
but so that they understand
that it allows you to store,

341
00:15:51,890 --> 00:15:55,570
for instance, in this case more
structured data, and not just flat

342
00:15:55,570 --> 00:15:58,990
row-by-row based data instead.

343
00:15:58,990 --> 00:16:01,607
Cloud computing-- a topic, too,
that's distinct to this class.

344
00:16:01,607 --> 00:16:03,940
And we talk about some of the
biggest players out there.

345
00:16:03,940 --> 00:16:07,960
What can Amazon, Google, Microsoft, and
others do for you and your business?

346
00:16:07,960 --> 00:16:12,490
And we talk about some of the
technologies and principles

347
00:16:12,490 --> 00:16:16,220
that underlie cloud computing
that someone has to understand.

348
00:16:16,220 --> 00:16:19,540
And so we talk about scaling and
replication and containerization

349
00:16:19,540 --> 00:16:22,660
and virtualization-- a lot
of the alphabet soup here--

350
00:16:22,660 --> 00:16:26,500
so that, again, when it comes to
asking questions of their engineers

351
00:16:26,500 --> 00:16:28,900
or trusting in the correctness
of their decisions,

352
00:16:28,900 --> 00:16:33,000
they at least understand how their own
servers or applications or products

353
00:16:33,000 --> 00:16:33,680
work.

354
00:16:33,680 --> 00:16:35,980
Even if it's at this
level of abstraction,

355
00:16:35,980 --> 00:16:41,180
they're not completely dependent on
the technical savvy only of others.

356
00:16:41,180 --> 00:16:43,730
So I'm a little worried this
URL is not going to work either.

357
00:16:43,730 --> 00:16:45,390
But allow me to--

358
00:16:45,390 --> 00:16:46,870
oh, this one does work.

359
00:16:46,870 --> 00:16:50,560
So this one is a sample
assessment from the end

360
00:16:50,560 --> 00:16:53,740
of this business-oriented class,
if you'd like to take a look.

361
00:16:53,740 --> 00:16:56,350
Again, I'll open up the
other one in just a bit.

362
00:16:56,350 --> 00:17:00,020
But again, the goals of the
class are a bit different.

363
00:17:00,020 --> 00:17:05,079
To recap, T is more about technology for
everyone from more of a consumer angle.

364
00:17:05,079 --> 00:17:10,780
B is more about business-type mindsets
and how you might use technology

365
00:17:10,780 --> 00:17:13,450
to make better decisions.

366
00:17:13,450 --> 00:17:17,230
But the audiences can
certainly be one and the same.

367
00:17:17,230 --> 00:17:22,300
Before I forge ahead to a third
and final precursor to CS50 itself,

368
00:17:22,300 --> 00:17:28,640
any questions or comments
here that I can answer?

369
00:17:28,640 --> 00:17:29,480
No?

370
00:17:29,480 --> 00:17:34,310
All right, seeing none, allow me to
give you the third and final short-form

371
00:17:34,310 --> 00:17:36,060
course that might proceed CS50--

372
00:17:36,060 --> 00:17:38,060
CS50 for lawyers, so to speak.

373
00:17:38,060 --> 00:17:41,270
So this course of the
three we've now discussed

374
00:17:41,270 --> 00:17:44,420
is a bit longer than the
others with more detail

375
00:17:44,420 --> 00:17:50,490
and goes into more discussion of topics
that intersect technology with society.

376
00:17:50,490 --> 00:17:53,690
The original target audience was,
indeed, law students or lawyers.

377
00:17:53,690 --> 00:17:55,735
But here, too, there are
wonderful opportunities

378
00:17:55,735 --> 00:17:57,860
I think for high school or
even middle school level

379
00:17:57,860 --> 00:18:00,530
to focus on some of those
exact intersections.

380
00:18:00,530 --> 00:18:02,802
And I'll give you a
few examples of those.

381
00:18:02,802 --> 00:18:04,760
In terms of the syllabus,
it's a little longer,

382
00:18:04,760 --> 00:18:07,610
and it's structured along the
lines of these topics here.

383
00:18:07,610 --> 00:18:10,640
But as with the business class,
we begin with some commonalities.

384
00:18:10,640 --> 00:18:13,940
We introduce students first to
computational thinking, as before.

385
00:18:13,940 --> 00:18:17,000
But we get them thinking more
about representation of not just

386
00:18:17,000 --> 00:18:21,880
ASCII or English, which had
its start with just seven bits.

387
00:18:21,880 --> 00:18:24,920
But we get them thinking about
Unicode and larger character sets

388
00:18:24,920 --> 00:18:28,010
and the implications for
internationalization and representation

389
00:18:28,010 --> 00:18:29,660
of other languages as well.

390
00:18:29,660 --> 00:18:32,540
We talk about algorithms, but
we also spend a bit more time

391
00:18:32,540 --> 00:18:35,480
helping them think about some
of the primitives that might

392
00:18:35,480 --> 00:18:37,550
underlie how you implement algorithms.

393
00:18:37,550 --> 00:18:40,460
For instance, we spend more
time talking about abstraction.

394
00:18:40,460 --> 00:18:42,755
On the screen here is, of course, what?

395
00:18:42,755 --> 00:18:46,370
What does anyone see, if you'd like
to shout it out or raise your hand?

396
00:18:46,370 --> 00:18:46,870
Anyone?

397
00:18:46,870 --> 00:18:48,272
Not a trick question.

398
00:18:48,272 --> 00:18:48,980
AUDIENCE: A cube.

399
00:18:48,980 --> 00:18:50,270
DAVID MALAN: A cube, I heard.

400
00:18:50,270 --> 00:18:51,830
So it's indeed a cube.

401
00:18:51,830 --> 00:18:56,400
And really, you know that, you say
that, because we all have in our minds

402
00:18:56,400 --> 00:18:58,820
the definition of some
abstraction of what a cube is.

403
00:18:58,820 --> 00:19:02,840
But frankly, what I am seeing
is maybe three diamonds

404
00:19:02,840 --> 00:19:04,670
that are all touching each other.

405
00:19:04,670 --> 00:19:08,930
Or what I'm seeing is a diagonal
line and another diagonal line

406
00:19:08,930 --> 00:19:11,690
and two more diagonal lines
that connect with each other.

407
00:19:11,690 --> 00:19:15,200
And you can imagine really getting into
the weeds of describing what you see.

408
00:19:15,200 --> 00:19:18,500
But thankfully, as [? Momadu ?] notes,
we have an abstraction known as a cube.

409
00:19:18,500 --> 00:19:22,340
And so we get students thinking about
the utility of these abstractions

410
00:19:22,340 --> 00:19:26,030
versus the price you pay by not
getting into the weeds of what

411
00:19:26,030 --> 00:19:29,030
it is you're trying to say, and
appreciating what computers can do

412
00:19:29,030 --> 00:19:32,150
and can't do when it comes
to following commands.

413
00:19:32,150 --> 00:19:34,340
We talk about programming
languages as before,

414
00:19:34,340 --> 00:19:37,940
but we go into a little more detail
in the context of the law class,

415
00:19:37,940 --> 00:19:40,910
looking first at a
higher-level language like C,

416
00:19:40,910 --> 00:19:43,610
looking at a lower-level
language like assembly language,

417
00:19:43,610 --> 00:19:46,410
and looking at the lowest of
languages, like machine code,

418
00:19:46,410 --> 00:19:47,900
which is just 0's and 1's.

419
00:19:47,900 --> 00:19:51,290
And we do this so that aspiring
attorneys down the road

420
00:19:51,290 --> 00:19:54,560
actually have a better understanding
of intellectual property, what

421
00:19:54,560 --> 00:19:58,430
it might mean for someone's code to be
similar to another, what it might mean

422
00:19:58,430 --> 00:20:01,110
for someone's algorithm to
be identical to another,

423
00:20:01,110 --> 00:20:04,400
just to that they have this bottom-up
understanding of those principles.

424
00:20:04,400 --> 00:20:06,380
And they don't have to
just take for granted

425
00:20:06,380 --> 00:20:10,190
that, oh, an algorithm is step-by-step
instructions for solving some problem.

426
00:20:10,190 --> 00:20:12,350
But what does that really
mean when computers

427
00:20:12,350 --> 00:20:16,040
and companies and owners and
intellectual property gets involved?

428
00:20:16,040 --> 00:20:18,380
We talk about the
limitations of computers.

429
00:20:18,380 --> 00:20:22,100
1999 was a problematic year, a.k.a.

430
00:20:22,100 --> 00:20:25,310
Y2K, because so many
companies and so many products

431
00:20:25,310 --> 00:20:28,460
were using just two digits to
store years instead of four.

432
00:20:28,460 --> 00:20:31,670
And so bad things might have
very well happened on scale.

433
00:20:31,670 --> 00:20:34,040
We talk about floating point values--

434
00:20:34,040 --> 00:20:36,320
numbers that have
decimal points in them--

435
00:20:36,320 --> 00:20:39,950
and give real-world examples
where failure to appreciate

436
00:20:39,950 --> 00:20:44,330
or failure to protect against
these realities of computing

437
00:20:44,330 --> 00:20:46,550
can lead to potentially
catastrophic failures.

438
00:20:46,550 --> 00:20:53,810
Here's a Boeing 737, I believe,
that essentially would turn off

439
00:20:53,810 --> 00:20:59,930
after 248 days in the sky because a
32-bit counter, a variable in memory,

440
00:20:59,930 --> 00:21:01,310
would overflow potentially.

441
00:21:01,310 --> 00:21:02,750
And bad things would happen.

442
00:21:02,750 --> 00:21:04,700
And the solution in the
short-term from Boeing

443
00:21:04,700 --> 00:21:08,810
was literally reboot your
planes every 247 days.

444
00:21:08,810 --> 00:21:12,770
So we get students thinking about
how software decisions and hardware

445
00:21:12,770 --> 00:21:16,800
limitations might have very
significant real-world ramifications.

446
00:21:16,800 --> 00:21:19,550
We talk in a bit more depth about
algorithms and data structures--

447
00:21:19,550 --> 00:21:24,470
more similar, if you will,
to CS50 itself and CS50AP.

448
00:21:24,470 --> 00:21:28,460
We go into things like bubble sort,
for instance, or selection sort,

449
00:21:28,460 --> 00:21:30,900
for instance, or really
sorting in general.

450
00:21:30,900 --> 00:21:34,310
We talk about data structures as
they are incarnated in languages,

451
00:21:34,310 --> 00:21:38,060
like Python having dictionaries
and lists and other such things.

452
00:21:38,060 --> 00:21:40,450
And then we go into more
detail on cryptography.

453
00:21:40,450 --> 00:21:42,200
We, of course, spend
a bit of time on this

454
00:21:42,200 --> 00:21:47,360
in CS50 itself with Caesar or Vigenere
or few such problem sets as well.

455
00:21:47,360 --> 00:21:49,885
But we spend a bit
more formality on this,

456
00:21:49,885 --> 00:21:52,760
getting students thinking about what
it means to encrypt information,

457
00:21:52,760 --> 00:21:55,670
whether it's with substitution
ciphers, whether it's

458
00:21:55,670 --> 00:21:58,940
an attack on the same using
so-called "frequency analysis."

459
00:21:58,940 --> 00:22:02,840
And we get students thinking a
little more adversarily about some

460
00:22:02,840 --> 00:22:05,350
of the technology that
they might build in CS50,

461
00:22:05,350 --> 00:22:09,740
but might not necessarily think twice
about at that point in the course.

462
00:22:09,740 --> 00:22:12,560
We talk about what it
means to hash passwords.

463
00:22:12,560 --> 00:22:15,660
Not just encrypting data, but
hashing them in one direction,

464
00:22:15,660 --> 00:22:19,880
and what it might mean if a company's
database is hacked or compromised,

465
00:22:19,880 --> 00:22:23,270
and what the threats to a
customer's privacy might be.

466
00:22:23,270 --> 00:22:26,360
We talk about encryption a bit more
mathematically, a bit more formally,

467
00:22:26,360 --> 00:22:29,700
in the context of, say, public-key
cryptography, if you're familiar.

468
00:22:29,700 --> 00:22:31,500
And we talk about
digital signatures, which

469
00:22:31,500 --> 00:22:34,530
is sort of an opposite application
of the same technology,

470
00:22:34,530 --> 00:22:39,330
in order to prove mathematically
that I am who I claim to be.

471
00:22:39,330 --> 00:22:42,210
We intersect with more modern
technologies like Blockchain

472
00:22:42,210 --> 00:22:46,140
and cryptocurrencies like Bitcoin
and the like and help students

473
00:22:46,140 --> 00:22:49,380
understand what is interesting
about those technologically

474
00:22:49,380 --> 00:22:52,200
and what kinds of problems
they can actually solve.

475
00:22:52,200 --> 00:22:54,870
And we talk about cybersecurity
in much more detail,

476
00:22:54,870 --> 00:22:58,470
too, when we talk about
how hardware itself--

477
00:22:58,470 --> 00:23:01,050
what various hardware components
inside of a computer do,

478
00:23:01,050 --> 00:23:05,230
and which of those are potential threats
to one's privacy if, for instance,

479
00:23:05,230 --> 00:23:08,520
someone has physical access to
the memory or some other device.

480
00:23:08,520 --> 00:23:11,790
We talk about deleting files,
be it on Mac OS or Windows.

481
00:23:11,790 --> 00:23:13,830
And just emptying the
recycle bin or trash can

482
00:23:13,830 --> 00:23:16,492
is not really the best
way to cover your tracks

483
00:23:16,492 --> 00:23:17,950
or to remove sensitive information.

484
00:23:17,950 --> 00:23:20,010
And we help students understand why.

485
00:23:20,010 --> 00:23:22,650
We talk about how you might
intercept network traffic--

486
00:23:22,650 --> 00:23:26,170
everyone uses WiFi or
mobile networks these days--

487
00:23:26,170 --> 00:23:29,870
and what it might mean to use
things like HTTPS for encryption.

488
00:23:29,870 --> 00:23:32,130
And then we spend a bit more
time intercepting things

489
00:23:32,130 --> 00:23:35,640
like the primitives that underlie
internet technologies as they

490
00:23:35,640 --> 00:23:38,620
relate to bigger-picture
uses of cloud computing.

491
00:23:38,620 --> 00:23:41,910
And we talk quite simply about how
you get data from point A to point B.

492
00:23:41,910 --> 00:23:45,300
But then we start talking about how
you get a lot of data from point A

493
00:23:45,300 --> 00:23:47,610
to point B, maybe with
one server initially,

494
00:23:47,610 --> 00:23:50,040
or a bigger server as load scales.

495
00:23:50,040 --> 00:23:53,850
And we talk about horizontal
scalability, vertical scalability,

496
00:23:53,850 --> 00:23:57,732
and the kinds of approaches you can
take to solving some problem, even

497
00:23:57,732 --> 00:23:59,190
if you're not an engineer yourself.

498
00:23:59,190 --> 00:24:01,140
Maybe you're just the
one with the checkbook.

499
00:24:01,140 --> 00:24:04,860
But you need to decide, are you going
to get a lot of really cheap machines?

500
00:24:04,860 --> 00:24:07,590
Are you going to get a few
really beefed-up machines?

501
00:24:07,590 --> 00:24:11,410
And what are the trade-offs, being
the operative word, going to be?

502
00:24:11,410 --> 00:24:14,820
And then, again, we talk in a bit more
detail about very modern technologies

503
00:24:14,820 --> 00:24:17,890
like virtualization and
containerization-- which, as an aside,

504
00:24:17,890 --> 00:24:20,310
if unfamiliar, you've
been using for some time.

505
00:24:20,310 --> 00:24:24,120
Whether you use CS50 IDE or any
other tools, they're out there.

506
00:24:24,120 --> 00:24:27,840
And we help students understand
those building blocks.

507
00:24:27,840 --> 00:24:30,960
And then lastly, at the
tail-end of CS50 for lawyers,

508
00:24:30,960 --> 00:24:34,800
do we introduce students-- as often
we do-- to a bit of web development

509
00:24:34,800 --> 00:24:36,770
and helping them understand HTML.

510
00:24:36,770 --> 00:24:39,960
We spend a bit more time on
JavaScript and that event-based model

511
00:24:39,960 --> 00:24:43,770
I alluded to before, clicking
and dragging and changing things

512
00:24:43,770 --> 00:24:46,680
on the screen, and how you write
code to interact with humans.

513
00:24:46,680 --> 00:24:48,970
We talk a bit more
about database design--

514
00:24:48,970 --> 00:24:52,410
so not just using SQL,
but using it efficiently,

515
00:24:52,410 --> 00:24:57,090
designing and choosing the types
of your language more aptly,

516
00:24:57,090 --> 00:25:00,750
and even more sophisticated techniques
like transactions and locks.

517
00:25:00,750 --> 00:25:03,250
How do you assure the
integrity of your data,

518
00:25:03,250 --> 00:25:05,220
especially when you have
a lot of it coming in,

519
00:25:05,220 --> 00:25:07,412
especially for popular
websites and tools?

520
00:25:07,412 --> 00:25:09,120
And then at the very
end of the semester,

521
00:25:09,120 --> 00:25:11,520
do we revisit and reconnect
some of the topics,

522
00:25:11,520 --> 00:25:15,690
talking about things like denial of
service attacks on scale on the cloud,

523
00:25:15,690 --> 00:25:19,950
talking about defenses or potential
weaknesses like SSL or TLS,

524
00:25:19,950 --> 00:25:25,320
talking about more precise attacks using
code-- cross-site scripting attacks,

525
00:25:25,320 --> 00:25:28,830
where someone tricks you into
executing code in your users' browsers

526
00:25:28,830 --> 00:25:30,660
that they provided to you.

527
00:25:30,660 --> 00:25:32,910
Or something like a
cross-site request forgery,

528
00:25:32,910 --> 00:25:37,590
where you trick a user into
sending a request to a website

529
00:25:37,590 --> 00:25:40,110
that they might not have even intended.

530
00:25:40,110 --> 00:25:44,310
And we talk, of course, about databases
as well, and hashing those passwords,

531
00:25:44,310 --> 00:25:45,660
and what that really means.

532
00:25:45,660 --> 00:25:48,730
We talk about SQL injection
attacks, threats against the same.

533
00:25:48,730 --> 00:25:50,490
We talk about Man in the Middle attacks.

534
00:25:50,490 --> 00:25:54,930
We talk about phishing and really
a whole lot of technologies

535
00:25:54,930 --> 00:25:56,110
intersecting with society.

536
00:25:56,110 --> 00:25:58,110
And indeed, what we do
at the end of the course,

537
00:25:58,110 --> 00:26:00,540
particularly by way of a
colleague of ours, Doug,

538
00:26:00,540 --> 00:26:03,780
we start talking about really
the real-world ethical issues

539
00:26:03,780 --> 00:26:07,020
and the legal issues that
result from these intersections.

540
00:26:07,020 --> 00:26:11,700
And so we consider implications of
open-source software and the licensing

541
00:26:11,700 --> 00:26:13,560
thereof and what you
need to be mindful of,

542
00:26:13,560 --> 00:26:15,900
and what the trade-offs
are of open-source software

543
00:26:15,900 --> 00:26:20,430
that everyone can see, or closed-source
software that no one can see.

544
00:26:20,430 --> 00:26:23,160
Talking about disruptive
technologies and things

545
00:26:23,160 --> 00:26:25,740
that the law hasn't
even caught up to yet.

546
00:26:25,740 --> 00:26:29,730
For instance, being able to 3D-print
guns that aren't even metallic

547
00:26:29,730 --> 00:26:33,330
and can't be detected anymore-- what
are the implications for society when

548
00:26:33,330 --> 00:26:35,940
now, anyone on the internet can
download something like that

549
00:26:35,940 --> 00:26:39,540
and, resources permitting,
just create their own threats?

550
00:26:39,540 --> 00:26:42,200
Digital privacy and tracking
certainly in the news,

551
00:26:42,200 --> 00:26:45,090
and ever more so today when
it comes to social networking

552
00:26:45,090 --> 00:26:47,070
sites and the implications for humans.

553
00:26:47,070 --> 00:26:50,010
AI and robotics are very
much on the horizon.

554
00:26:50,010 --> 00:26:52,830
And indeed, Brian, will soon
introduce a course on the same

555
00:26:52,830 --> 00:26:55,980
and what the implications
are for users in society.

556
00:26:55,980 --> 00:27:00,270
GDPR and data privacy laws here
and abroad are germane as well.

557
00:27:00,270 --> 00:27:02,700
And then Net Neutrality,
which keeps coming up

558
00:27:02,700 --> 00:27:04,800
from time to time,
particularly within the US,

559
00:27:04,800 --> 00:27:08,847
and what that means technologically,
and what that means for users.

560
00:27:08,847 --> 00:27:10,680
And here, too, I'm going
to cross my fingers

561
00:27:10,680 --> 00:27:14,100
and see if I gave the right
permissions for this one.

562
00:27:14,100 --> 00:27:15,560
This one, too, is successful.

563
00:27:15,560 --> 00:27:17,160
So I got two out of three.

564
00:27:17,160 --> 00:27:19,253
Let me give you this
sample assignments as well.

565
00:27:19,253 --> 00:27:20,670
And you'll notice the overlapping.

566
00:27:20,670 --> 00:27:24,180
So, in fact, allow me in closing,
before I turn the reins over to Colton,

567
00:27:24,180 --> 00:27:27,770
just to give you a sense now of the
similarities and differences here.

568
00:27:27,770 --> 00:27:32,180
We've looked at CS50B and
L and T here in succession.

569
00:27:32,180 --> 00:27:36,440
And here is the same syllabi from
each course, this time laid out

570
00:27:36,440 --> 00:27:39,500
from left to right in the
order in which we saw it.

571
00:27:39,500 --> 00:27:41,600
And I did my best to
color-code this to show

572
00:27:41,600 --> 00:27:43,532
you the similarities and differences.

573
00:27:43,532 --> 00:27:45,740
I realize the colors won't
necessarily stand out well

574
00:27:45,740 --> 00:27:47,040
for your eyes or your screen.

575
00:27:47,040 --> 00:27:49,680
So we'll document this
in another form, too.

576
00:27:49,680 --> 00:27:53,390
But essentially, I used the
same colors in each course

577
00:27:53,390 --> 00:27:57,450
to indicate that there is
significant overlap in those topics.

578
00:27:57,450 --> 00:28:01,400
So both B and L, for instance, in
pink, spend a good amount of time

579
00:28:01,400 --> 00:28:05,330
on computational thinking, as
they do on programming languages,

580
00:28:05,330 --> 00:28:06,680
as well as programming.

581
00:28:06,680 --> 00:28:10,070
So sometimes, the titles might
differ, but the concepts are the same.

582
00:28:10,070 --> 00:28:12,380
And so ultimately, each
of these three courses

583
00:28:12,380 --> 00:28:15,740
is available to be taught as
OpenCourseWare, either as maybe

584
00:28:15,740 --> 00:28:19,070
a freshman class, a middle school
class that introduces students

585
00:28:19,070 --> 00:28:21,530
to the world of computing
and computer science,

586
00:28:21,530 --> 00:28:25,310
or, as with any of the classes, you can
pick and choose things off the shelf

587
00:28:25,310 --> 00:28:30,150
and integrate them into your own
class, be it CS50AP or something else.

588
00:28:30,150 --> 00:28:34,580
But generally speaking, these are
more conceptually-oriented classes,

589
00:28:34,580 --> 00:28:38,510
more societally-oriented classes,
and more introductory than something

590
00:28:38,510 --> 00:28:43,910
like CS50X or, really, CS50AP itself.

591
00:28:43,910 --> 00:28:47,900
Any questions or comments
before we turn our attention

592
00:28:47,900 --> 00:28:54,970
to what students and teachers
can do after these on ramps?

593
00:28:54,970 --> 00:29:00,340
AUDIENCE: I was just thinking that if
there is a CS50 course for medicine,

594
00:29:00,340 --> 00:29:02,630
my students would love it.

595
00:29:02,630 --> 00:29:04,678
DAVID MALAN: So the one
course we don't have, OK.

596
00:29:04,678 --> 00:29:07,720
But we've actually been thinking about
that, if only because Harvard does

597
00:29:07,720 --> 00:29:08,670
have a Medical School.

598
00:29:08,670 --> 00:29:10,410
But it does not, I'm afraid, exist yet.

599
00:29:10,410 --> 00:29:13,300


600
00:29:13,300 --> 00:29:14,560
Other questions or comments?

601
00:29:14,560 --> 00:29:17,200


602
00:29:17,200 --> 00:29:17,850
No?

603
00:29:17,850 --> 00:29:20,290
Colton, would you like
to take the floor?

604
00:29:20,290 --> 00:29:21,880
COLTON OGDEN: Sure thing, awesome.

605
00:29:21,880 --> 00:29:24,680
So thanks, David, for the introduction.

606
00:29:24,680 --> 00:29:28,150
I'm going to talk about CS50G,
or GD50, as I like to call it--

607
00:29:28,150 --> 00:29:29,247
Game Development 50.

608
00:29:29,247 --> 00:29:31,080
I'm going to switch my
screen over here just

609
00:29:31,080 --> 00:29:34,330
to have a slightly better
view of the slides, here.

610
00:29:34,330 --> 00:29:37,980
So GD50 is a continuation after CS50.

611
00:29:37,980 --> 00:29:40,900
So the expectation by this
point will be that students

612
00:29:40,900 --> 00:29:43,360
do have some programming
experience, be that through CS50

613
00:29:43,360 --> 00:29:45,460
or through other equivalent courses.

614
00:29:45,460 --> 00:29:50,440
And GD50 or CS50's Intro to
Game Development is all about 2D

615
00:29:50,440 --> 00:29:51,877
and 3D games.

616
00:29:51,877 --> 00:29:53,710
So we spend a good chunk
of the course going

617
00:29:53,710 --> 00:29:55,480
through a lot of really famous
titles that you probably

618
00:29:55,480 --> 00:29:58,630
see around the screen like Super
Mario Brothers, Legend of Zelda,

619
00:29:58,630 --> 00:29:59,607
Angry Birds, Pokemon.

620
00:29:59,607 --> 00:30:01,690
But we also do a little
bit of 3D game development

621
00:30:01,690 --> 00:30:04,330
at the very end in Unity Game Engine--

622
00:30:04,330 --> 00:30:09,400
Dreadhalls, Portal, and a helicopter
game in 3D being examples thereof.

623
00:30:09,400 --> 00:30:12,535
And this course uses a couple of
different programming languages.

624
00:30:12,535 --> 00:30:14,410
And I think this is
actually pretty important

625
00:30:14,410 --> 00:30:17,050
because in real-world
industry, it's pretty common

626
00:30:17,050 --> 00:30:20,080
that between companies and
even within the same project,

627
00:30:20,080 --> 00:30:22,927
you'll be expected to use-- and
even within the same game project,

628
00:30:22,927 --> 00:30:24,760
for the sake of this
course at least, you'll

629
00:30:24,760 --> 00:30:28,120
be expected to use not just one
language, but multiple languages.

630
00:30:28,120 --> 00:30:30,070
So here, we have Lua and Love 2D.

631
00:30:30,070 --> 00:30:32,410
That's what that symbol is
there on the left-hand side

632
00:30:32,410 --> 00:30:34,810
to represent the 2D
section of the course.

633
00:30:34,810 --> 00:30:37,780
And on the right-hand side,
we have C # and Unity,

634
00:30:37,780 --> 00:30:40,910
which represent the
3D side of the course.

635
00:30:40,910 --> 00:30:42,370
So we start things off with Pong.

636
00:30:42,370 --> 00:30:44,740
And this is a very
quintessential, classic game.

637
00:30:44,740 --> 00:30:47,860
But this really is students'--
we can presume many, for them,

638
00:30:47,860 --> 00:30:50,620
their first dive into
something as graphical as this.

639
00:30:50,620 --> 00:30:52,810
And it made sense to take
things in a progression

640
00:30:52,810 --> 00:30:55,590
from really, really simple
to more complicated.

641
00:30:55,590 --> 00:30:57,520
And pong is a very
suitable first example

642
00:30:57,520 --> 00:31:02,650
as well because it's the grandfather
progenitor of the video game industry.

643
00:31:02,650 --> 00:31:07,570
So the sake of this example, really,
is to showcase very basic things

644
00:31:07,570 --> 00:31:09,520
like getting something
visual on the screen

645
00:31:09,520 --> 00:31:12,370
to begin with, where students
may only have thus far done

646
00:31:12,370 --> 00:31:14,547
textual CLI-based programming.

647
00:31:14,547 --> 00:31:17,380
We have text being rendered on the
screen, but not through a command

648
00:31:17,380 --> 00:31:18,040
prompt.

649
00:31:18,040 --> 00:31:21,127
And we have various things like game
state, so managing what we're doing,

650
00:31:21,127 --> 00:31:23,210
whether it's the beginning
or the end of the game.

651
00:31:23,210 --> 00:31:25,730
And this is a very common
theme in programming.

652
00:31:25,730 --> 00:31:27,940
And this is-- effectively,
state machines

653
00:31:27,940 --> 00:31:31,450
are an important concept in computer
science, generally speaking.

654
00:31:31,450 --> 00:31:34,450
We transition from that to something
a little more visually interesting.

655
00:31:34,450 --> 00:31:37,960
So this is where we can start to have
students actually use their own art

656
00:31:37,960 --> 00:31:39,790
or at least get a
sense of how to do that

657
00:31:39,790 --> 00:31:41,748
and have it actually move
around on the screen.

658
00:31:41,748 --> 00:31:43,870
So we cover things
like delta time, which

659
00:31:43,870 --> 00:31:47,170
just means the difference between
two frames in milliseconds, which

660
00:31:47,170 --> 00:31:49,940
allows us to then calculate
things like gravity,

661
00:31:49,940 --> 00:31:52,690
which is a frame by frame calculation.

662
00:31:52,690 --> 00:31:57,880
After that, we go to breakout, which
is a continuation of one and two--

663
00:31:57,880 --> 00:31:59,170
rather, lectures 0 and 1--

664
00:31:59,170 --> 00:32:03,610
Pong and Flappy Bird, where we've
taken the basic idea of Pong,

665
00:32:03,610 --> 00:32:05,740
and we've taken the idea
of adding in sprites.

666
00:32:05,740 --> 00:32:08,500
But we've also made the
game a lot more complicated.

667
00:32:08,500 --> 00:32:12,490
And this I like to use is an example
of what's called procedural generation.

668
00:32:12,490 --> 00:32:14,793
So we're doing things, not
just necessarily putting

669
00:32:14,793 --> 00:32:16,960
graphics on the screen, but
talking about algorithms

670
00:32:16,960 --> 00:32:21,640
that let us generate data or
information to make games playable,

671
00:32:21,640 --> 00:32:24,978
one iteration after another, which
I thought was an interesting thing.

672
00:32:24,978 --> 00:32:26,770
It's something that
I'm personally attached

673
00:32:26,770 --> 00:32:28,300
to with games and with programming.

674
00:32:28,300 --> 00:32:31,690
And it makes things a little
bit more, I think, rigorous.

675
00:32:31,690 --> 00:32:34,887
And ties it to something that's not,
strictly speaking, necessary to games

676
00:32:34,887 --> 00:32:36,970
because you can do the
same thing with a database.

677
00:32:36,970 --> 00:32:38,970
You could generate your
own database information

678
00:32:38,970 --> 00:32:42,280
if you were testing something
on the web, for example.

679
00:32:42,280 --> 00:32:47,500
We go into match 3, which
is a discrete style--

680
00:32:47,500 --> 00:32:51,220
not really a board game, but
it's a discrete style game where

681
00:32:51,220 --> 00:32:53,170
you swap tiles and try to get matches.

682
00:32:53,170 --> 00:32:55,510
And this illustrates a
different kind of programming,

683
00:32:55,510 --> 00:32:57,910
where you're looking at
a finite space and trying

684
00:32:57,910 --> 00:33:01,210
to calculate whether a particular
rule or condition is met,

685
00:33:01,210 --> 00:33:04,510
and then changing the game board,
one iteration after another.

686
00:33:04,510 --> 00:33:05,620
So it's just kind of--

687
00:33:05,620 --> 00:33:09,880
at least with this example, I liked
it because it was a popular thing.

688
00:33:09,880 --> 00:33:13,240
Again, the whole idea or
philosophy of the course

689
00:33:13,240 --> 00:33:16,440
is that it should be
a case study approach

690
00:33:16,440 --> 00:33:20,080
to the course, where we have
a full corpus of source code

691
00:33:20,080 --> 00:33:20,960
that you dive into.

692
00:33:20,960 --> 00:33:23,800
But it's also varied so that
the students aren't necessarily

693
00:33:23,800 --> 00:33:26,323
getting the same type of game
throughout the whole course.

694
00:33:26,323 --> 00:33:28,240
They're getting to sample
the landscape, which

695
00:33:28,240 --> 00:33:31,360
was a major design philosophy of GD50.

696
00:33:31,360 --> 00:33:35,680
DAVID MALAN: Angela asked earlier,
how many girls play these games?

697
00:33:35,680 --> 00:33:41,170
And does the course cover the work
issues that face game designers?

698
00:33:41,170 --> 00:33:42,310
COLTON OGDEN: I imagine--

699
00:33:42,310 --> 00:33:46,510
I haven't done the research to
know the gender distribution.

700
00:33:46,510 --> 00:33:49,810
I believe I read stats on
mobile games-- in particular,

701
00:33:49,810 --> 00:33:54,160
things like Candy Crush and many other
types of games on mobile were very--

702
00:33:54,160 --> 00:33:57,160
actually, I think more women
played those than men, if I

703
00:33:57,160 --> 00:33:59,423
remember reading a study about that.

704
00:33:59,423 --> 00:34:00,340
I'm not entirely sure.

705
00:34:00,340 --> 00:34:04,010
I don't want to say anything
incorrect as regards that.

706
00:34:04,010 --> 00:34:08,520
I feel like the games industry
is a little bit more male-skewed.

707
00:34:08,520 --> 00:34:11,409
Although I think within
the last five to 10 years,

708
00:34:11,409 --> 00:34:14,199
it seems like it has gotten
a little bit more balanced.

709
00:34:14,199 --> 00:34:18,250
But there's still a bit
of a discrepancy for sure.

710
00:34:18,250 --> 00:34:21,909
In terms of the
workplace considerations,

711
00:34:21,909 --> 00:34:24,628
we don't really cover that as much.

712
00:34:24,628 --> 00:34:27,670
It's an interesting thing that would
be maybe worth adding to the course,

713
00:34:27,670 --> 00:34:28,170
actually.

714
00:34:28,170 --> 00:34:31,810
But currently, no, we do not talk
about that-- at least not in detail,

715
00:34:31,810 --> 00:34:34,790
as far as I recall during lecture,
unless it was asked as a question.

716
00:34:34,790 --> 00:34:35,290
Sure.

717
00:34:35,290 --> 00:34:37,082
DAVID MALAN: And Colton,
[? Amira ?] asked,

718
00:34:37,082 --> 00:34:40,731
is this course considered
to be advanced?

719
00:34:40,731 --> 00:34:45,810
COLTON OGDEN: I would say it'd
probably be intermediate level.

720
00:34:45,810 --> 00:34:49,489
It's hard for me to put
a specific label on it.

721
00:34:49,489 --> 00:34:51,322
Certainly, it's more
advanced than-- well, I

722
00:34:51,322 --> 00:34:54,489
didn't want to say it's more advanced
than CS50 is because CS50's relatively

723
00:34:54,489 --> 00:34:56,179
advanced for an entry-level course.

724
00:34:56,179 --> 00:34:58,370
I would say it approaches
the level of difficulty

725
00:34:58,370 --> 00:35:01,520
maybe as the later stages of CS50.

726
00:35:01,520 --> 00:35:05,510
In some regards, maybe slightly
more difficult because we're dealing

727
00:35:05,510 --> 00:35:07,160
with larger code bases on average.

728
00:35:07,160 --> 00:35:09,470
Actually, most of the
code bases in GD50 are

729
00:35:09,470 --> 00:35:12,590
upwards of 1,000 lines--
maybe 2,000 lines of code.

730
00:35:12,590 --> 00:35:17,300
And this was deliberately the case,
because at least with the design

731
00:35:17,300 --> 00:35:20,602
philosophy that I had
going in, I did not want--

732
00:35:20,602 --> 00:35:22,310
or as I was learning
game development, it

733
00:35:22,310 --> 00:35:24,890
was very hard for me to
find large code bases

734
00:35:24,890 --> 00:35:26,705
like the complete
picture of what a game is

735
00:35:26,705 --> 00:35:28,330
and how all the pieces worked together.

736
00:35:28,330 --> 00:35:31,100
I could very easily
find tutorials online

737
00:35:31,100 --> 00:35:34,280
that would illustrate one concept, like
how to move something on the screen

738
00:35:34,280 --> 00:35:37,518
or how to transition between
two different scenes, maybe.

739
00:35:37,518 --> 00:35:39,560
But very rarely would I
actually have a full code

740
00:35:39,560 --> 00:35:42,710
base that was representative of
what an entire game might look like,

741
00:35:42,710 --> 00:35:46,880
or at least a proof of concept there
that was relatively fleshed out.

742
00:35:46,880 --> 00:35:50,750
And you could easily add more content
to it to make a proper, full game.

743
00:35:50,750 --> 00:35:55,680
So yeah, in that sense, students will be
expected to navigate large code bases.

744
00:35:55,680 --> 00:35:59,675
And the assignments therefore are
a little bit smaller than obviously

745
00:35:59,675 --> 00:36:01,050
implementing an entire code base.

746
00:36:01,050 --> 00:36:02,675
They're usually adding a small feature.

747
00:36:02,675 --> 00:36:05,300
For example, in Pong, the
objective for the student

748
00:36:05,300 --> 00:36:07,537
is to just simply add
an AI to the paddle

749
00:36:07,537 --> 00:36:09,620
on the right-hand side
that lets it track the ball

750
00:36:09,620 --> 00:36:12,380
or have some behavior that the
student wishes, whether it's

751
00:36:12,380 --> 00:36:16,310
to make it behave somewhat like
a human or to be infallible,

752
00:36:16,310 --> 00:36:18,240
which is often the case.

753
00:36:18,240 --> 00:36:19,880
But, yeah, generally, that's the case--

754
00:36:19,880 --> 00:36:24,620
large code bases to navigate, which
might be a difference from CS50.

755
00:36:24,620 --> 00:36:26,450
But the assignment
rigor in and of itself

756
00:36:26,450 --> 00:36:30,342
is probably comparable to mid
to late CS50 in difficulty.

757
00:36:30,342 --> 00:36:33,050
DAVID MALAN: And Steve, to your
point about it being too advanced

758
00:36:33,050 --> 00:36:35,660
for middle schoolers, it
does assume, to be clear,

759
00:36:35,660 --> 00:36:37,790
as will Brian's classes,
that students have taken

760
00:36:37,790 --> 00:36:40,340
CS50 itself or some equivalent.

761
00:36:40,340 --> 00:36:43,520
So it assumes that degree of comfort
and sophistication out of the gate,

762
00:36:43,520 --> 00:36:44,185
to be clear.

763
00:36:44,185 --> 00:36:45,060
COLTON OGDEN: Indeed.

764
00:36:45,060 --> 00:36:45,680
DAVID MALAN: Colton, back to you.

765
00:36:45,680 --> 00:36:46,563
I think we caught up.

766
00:36:46,563 --> 00:36:47,480
COLTON OGDEN: Awesome.

767
00:36:47,480 --> 00:36:48,767
Thank you so much.

768
00:36:48,767 --> 00:36:50,600
So I was talking about
Super Mario Brothers,

769
00:36:50,600 --> 00:36:53,660
which was the influence of the
course from the very beginning.

770
00:36:53,660 --> 00:36:56,310
I probably mentioned all of that stuff.

771
00:36:56,310 --> 00:36:58,490
But the big thing that
I wanted to hammer home

772
00:36:58,490 --> 00:37:01,070
was the idea of illusions--
how games in and of themselves

773
00:37:01,070 --> 00:37:03,650
usually are meant to
trick us into thinking

774
00:37:03,650 --> 00:37:06,590
that we are in a particular
place or doing a particular thing

775
00:37:06,590 --> 00:37:08,750
as a particular entity.

776
00:37:08,750 --> 00:37:12,390
In the case of Super Mario
Brothers, in this case,

777
00:37:12,390 --> 00:37:15,410
at least we are typically
rendering the entire thing at once.

778
00:37:15,410 --> 00:37:18,380
But typically with games,
outside of the camera bounds,

779
00:37:18,380 --> 00:37:21,350
you will not have tiles being
rendered to save on memory

780
00:37:21,350 --> 00:37:26,000
and to save on rendering-- for the GPU
you to not have to render more texture

781
00:37:26,000 --> 00:37:27,830
or bits of textures.

782
00:37:27,830 --> 00:37:30,380
In the case of Flappy Bird,
if you were to zoom way out

783
00:37:30,380 --> 00:37:34,130
of the example of Flappy Bird, you
would see these long weird pipes,

784
00:37:34,130 --> 00:37:37,730
and then just a simple image that
was infinitely scrolling to make us

785
00:37:37,730 --> 00:37:40,940
feel like we're actually
moving through space.

786
00:37:40,940 --> 00:37:42,020
But in fact, we're not.

787
00:37:42,020 --> 00:37:45,830
And actually, the pipes are getting
generated and shifted back and forth

788
00:37:45,830 --> 00:37:50,503
around the screen as needed to get
the effect that we're looking for.

789
00:37:50,503 --> 00:37:52,170
So that was it for Super Mario Brothers.

790
00:37:52,170 --> 00:37:54,020
Now, let's go over to Legend of Zelda.

791
00:37:54,020 --> 00:37:59,180
So Zelda is a another game of that
era where it was released for the NES.

792
00:37:59,180 --> 00:38:01,670
And it has a similar almost
aesthetic of the era.

793
00:38:01,670 --> 00:38:03,500
But this gives you
really a top down games.

794
00:38:03,500 --> 00:38:08,645
And the real purpose of this lecture,
amongst a couple of little minor things

795
00:38:08,645 --> 00:38:10,520
that we talked about
graphically, was that we

796
00:38:10,520 --> 00:38:13,932
wanted to discuss how we could
model things like creatures as data.

797
00:38:13,932 --> 00:38:16,640
So we could have these things like
these ghosts and these spiders

798
00:38:16,640 --> 00:38:21,350
and these slimes actually modeled
in a config file, more or less.

799
00:38:21,350 --> 00:38:23,660
And we would just dynamically
load them in, rather than

800
00:38:23,660 --> 00:38:26,330
have to write a lot of different
logic or repeated logic

801
00:38:26,330 --> 00:38:33,440
or use a particular inheritance in the
object-oriented sense, an inherited

802
00:38:33,440 --> 00:38:36,300
class, to model all of
these individual creatures.

803
00:38:36,300 --> 00:38:40,850
So data-driven design is a
big aspect of this lecture.

804
00:38:40,850 --> 00:38:44,480
And I want to believe that that
applies to a lot of domains,

805
00:38:44,480 --> 00:38:46,940
just like a lot of
these other concepts do,

806
00:38:46,940 --> 00:38:51,598
beyond the world of game development,
like in web development, for example.

807
00:38:51,598 --> 00:38:53,640
We transition completely
in a different direction

808
00:38:53,640 --> 00:38:58,680
here to Angry Birds or an Angry Birds
style game using physics, 2D physics.

809
00:38:58,680 --> 00:38:59,940
Box 2D would be the name.

810
00:38:59,940 --> 00:39:04,260
And this was more to give students a
taste of a different outlying genre

811
00:39:04,260 --> 00:39:07,650
and a different way of building games
because building games with physics

812
00:39:07,650 --> 00:39:10,440
objects is very different
than a lot of what

813
00:39:10,440 --> 00:39:11,920
we've covered earlier in the class.

814
00:39:11,920 --> 00:39:14,170
So this is, again, part of
the idea of giving students

815
00:39:14,170 --> 00:39:19,260
just a wide taste of the landscape
as befits game development.

816
00:39:19,260 --> 00:39:22,477
And here, they learn things like how
to model different types of shapes

817
00:39:22,477 --> 00:39:24,060
and how they interact with each other.

818
00:39:24,060 --> 00:39:26,400
In this case, we have this
little barricade here,

819
00:39:26,400 --> 00:39:29,318
represented by these wooden boxes.

820
00:39:29,318 --> 00:39:31,110
And then we have the
characters themselves,

821
00:39:31,110 --> 00:39:36,240
with a model trajectory here, in
which case they'll collide with that.

822
00:39:36,240 --> 00:39:40,980
Following that is our last 2D game,
which is Pokemon, or a version thereof.

823
00:39:40,980 --> 00:39:45,955
Again, everything with this course is
all public domain sprites by design

824
00:39:45,955 --> 00:39:48,330
because we don't want to
infringe on anybody's copyright.

825
00:39:48,330 --> 00:39:51,210
But here, this is very
similarly modeling

826
00:39:51,210 --> 00:39:54,272
off of Pokemon, which was a very
famous game in the late '90s,

827
00:39:54,272 --> 00:39:55,980
where you capture
these little creatures.

828
00:39:55,980 --> 00:39:57,760
And you can fight them back and forth.

829
00:39:57,760 --> 00:40:01,830
And this was to help with a few
different things, particularly events

830
00:40:01,830 --> 00:40:06,120
and callback functions, which is a big
aspect of asynchronous programming.

831
00:40:06,120 --> 00:40:09,280
And also higher order or
functional programming,

832
00:40:09,280 --> 00:40:12,630
which was a different paradigm
that students might not

833
00:40:12,630 --> 00:40:16,322
be super-subjected to until
they've maybe taken CS50,

834
00:40:16,322 --> 00:40:18,780
because I believe with CS50,
and at least JavaScript, there

835
00:40:18,780 --> 00:40:19,960
is a bit of that.

836
00:40:19,960 --> 00:40:24,280
But here, Lua, because it's
a dynamic scripting language,

837
00:40:24,280 --> 00:40:27,030
it does have these features actually
very similar in a lot of ways

838
00:40:27,030 --> 00:40:27,990
to JavaScript.

839
00:40:27,990 --> 00:40:29,430
So Lua gives us the option.

840
00:40:29,430 --> 00:40:32,290
We can both test not only
turn-based combat systems

841
00:40:32,290 --> 00:40:35,220
and the idea of two entities
taking turns and making decisions

842
00:40:35,220 --> 00:40:39,480
back and forth, but also a different
way of thinking about programming, which

843
00:40:39,480 --> 00:40:42,870
I thought was important to illustrate.

844
00:40:42,870 --> 00:40:46,620
And then following that, we
actually transition to Unity 3D.

845
00:40:46,620 --> 00:40:50,760
And this was by design
because it was a nice way

846
00:40:50,760 --> 00:40:54,090
to get students to use
a real-world toolkit.

847
00:40:54,090 --> 00:40:57,180
Not that Love 2D isn't real-world,
but Unity in particular

848
00:40:57,180 --> 00:41:01,320
is not only a game engine, but also
one of the most widely used game

849
00:41:01,320 --> 00:41:05,700
engines in the modern game
development ecosystem.

850
00:41:05,700 --> 00:41:08,070
And by doing that, we
let students actually

851
00:41:08,070 --> 00:41:12,780
use the tool that's highly in
vogue and get real-world skills,

852
00:41:12,780 --> 00:41:15,540
not only just use things that are
in a model or mock environment.

853
00:41:15,540 --> 00:41:18,150
And that's also, again, by design
throughout the entire course

854
00:41:18,150 --> 00:41:20,848
to give them a larger
code basis to work with.

855
00:41:20,848 --> 00:41:23,140
So here, we are creating just
a simple helicopter game.

856
00:41:23,140 --> 00:41:25,707
It's actually almost like
a 2D game in and of itself.

857
00:41:25,707 --> 00:41:28,290
But we have helicopters and
planes and the like moving around.

858
00:41:28,290 --> 00:41:29,460
So we're using models.

859
00:41:29,460 --> 00:41:33,300
We're doing basically just a tutorial
on how to use Unity for the most part

860
00:41:33,300 --> 00:41:35,910
and get our minds thinking
in 3D and using models

861
00:41:35,910 --> 00:41:39,530
rather than using 2D and sprites.

862
00:41:39,530 --> 00:41:42,350
Following that, we do a
first-person horror game.

863
00:41:42,350 --> 00:41:45,380
So this is Dreadhalls, which we
actually played in the office

864
00:41:45,380 --> 00:41:47,660
on a VR headset, which was a great time.

865
00:41:47,660 --> 00:41:49,550
And here, we talk about
first-person games.

866
00:41:49,550 --> 00:41:51,760
And this is very different,
obviously, from anything

867
00:41:51,760 --> 00:41:53,010
that we've done in the course.

868
00:41:53,010 --> 00:41:55,218
Now we're actually doing or
beginning to do something

869
00:41:55,218 --> 00:41:57,250
that's unique to the realm of 3D games.

870
00:41:57,250 --> 00:42:01,310
It's something that we couldn't--
unless we used faux 3D--

871
00:42:01,310 --> 00:42:04,310
2D-style implementations,
something that we could not

872
00:42:04,310 --> 00:42:07,730
do in 2D that we can now
do using Unity and 3D--

873
00:42:07,730 --> 00:42:11,060
that idea of navigating a world, an
actual world, and feeling like we're

874
00:42:11,060 --> 00:42:13,830
an actor or an agent in that space.

875
00:42:13,830 --> 00:42:17,780
And here, it's really just a horror
game, and then to model that idea.

876
00:42:17,780 --> 00:42:18,690
But it's a big step.

877
00:42:18,690 --> 00:42:20,607
And we can talk about
things like how to model

878
00:42:20,607 --> 00:42:22,940
a character moving around
and interacting with things

879
00:42:22,940 --> 00:42:24,350
and colliding with things.

880
00:42:24,350 --> 00:42:27,440
And this is applicable to all
kinds of different things.

881
00:42:27,440 --> 00:42:29,660
I even taught a seminar on--

882
00:42:29,660 --> 00:42:31,850
a workshop on how to use
a lot of these same ideas

883
00:42:31,850 --> 00:42:36,050
just to create a museum
navigational tool, which

884
00:42:36,050 --> 00:42:38,007
illustrates just how
powerful Unity is, even

885
00:42:38,007 --> 00:42:39,590
outside the world of game development.

886
00:42:39,590 --> 00:42:41,882
So if students want to maybe
learn the principles here,

887
00:42:41,882 --> 00:42:44,690
they could take this idea and
apply it to all sorts of domains.

888
00:42:44,690 --> 00:42:47,360
This doesn't have to necessarily
strictly be creating games.

889
00:42:47,360 --> 00:42:50,160
It could be any type of multimedia.

890
00:42:50,160 --> 00:42:53,863
And then the final lecture
of the course is a evolution

891
00:42:53,863 --> 00:42:56,780
of that last process, where we're
actually implementing a first-person

892
00:42:56,780 --> 00:42:59,700
shooter, but not in the
traditional sense of the term,

893
00:42:59,700 --> 00:43:04,580
but rather a clone of the game Portal,
which involves a portal gun, which

894
00:43:04,580 --> 00:43:07,020
shoots just these
portals on flat surfaces

895
00:43:07,020 --> 00:43:09,890
that you can then walk through
and then jump out the other side.

896
00:43:09,890 --> 00:43:12,710
This was meant to involve the
player in a little bit more

897
00:43:12,710 --> 00:43:16,580
of the technical aspects of using
Unity-- things like rendering textures,

898
00:43:16,580 --> 00:43:19,045
casting rays from the point
of view of the camera,

899
00:43:19,045 --> 00:43:21,920
and then finding what the nearest
collidable surface is-- things that

900
00:43:21,920 --> 00:43:25,410
would allow students to not just
simply create a thing to walk around,

901
00:43:25,410 --> 00:43:27,800
but that can actually
interact in dynamic ways

902
00:43:27,800 --> 00:43:30,020
with the surfaces in their game world.

903
00:43:30,020 --> 00:43:33,770
And that's basically it in terms of
the curriculum for the games course.

904
00:43:33,770 --> 00:43:35,870
Again, it's meant to be
a case study approach,

905
00:43:35,870 --> 00:43:43,410
where the concepts and the ideas
and the curriculum or the subjects

906
00:43:43,410 --> 00:43:47,570
therein are introduced in an organic way
to make it feel like they're navigating

907
00:43:47,570 --> 00:43:49,400
the process of becoming
a game developer,

908
00:43:49,400 --> 00:43:53,360
less so than they are maybe
learning it in a traditional, more

909
00:43:53,360 --> 00:43:54,620
austere sense of the term.

910
00:43:54,620 --> 00:43:57,050
It was a philosophy
that I personally wish

911
00:43:57,050 --> 00:43:59,310
existed when I was learning
how to game program.

912
00:43:59,310 --> 00:44:02,480
And so I figured it would
be a nice thing to try out.

913
00:44:02,480 --> 00:44:05,540
So yeah, that was it
for the game syllabus.

914
00:44:05,540 --> 00:44:07,730
And I think Brian is next,
but I'm happy to take

915
00:44:07,730 --> 00:44:10,330
any questions if anybody has any.

916
00:44:10,330 --> 00:44:13,250
SPEAKER: Some questions that
came up in the chat, Colton--

917
00:44:13,250 --> 00:44:15,920
Peter asks, "What
development environments

918
00:44:15,920 --> 00:44:20,120
are used for the courses on CS50 IDE?"

919
00:44:20,120 --> 00:44:22,640
COLTON OGDEN: So currently,
no, it's not in CS50 IDE.

920
00:44:22,640 --> 00:44:25,190
We expect the student, at
least for the Love 2D section,

921
00:44:25,190 --> 00:44:29,430
and even for the C # and Unity
section, to use a tool called VS Code,

922
00:44:29,430 --> 00:44:32,720
which is a very popular text editor
which has actually integration with

923
00:44:32,720 --> 00:44:35,923
Love 2D, where you can just
press Alt L or Command L,

924
00:44:35,923 --> 00:44:38,840
depending on whether you're using a
Mac, to actually fire up Love with

925
00:44:38,840 --> 00:44:40,507
your current project loaded immediately.

926
00:44:40,507 --> 00:44:44,690
So you just very quickly test back
and forth whether your code is working

927
00:44:44,690 --> 00:44:47,810
or not, which I personally really enjoy.

928
00:44:47,810 --> 00:44:49,370
And I use that almost exclusively.

929
00:44:49,370 --> 00:44:53,827
And Unity has its own built-in IDE,
more or less, with at least all

930
00:44:53,827 --> 00:44:55,910
of the visual aspects of
things, although it still

931
00:44:55,910 --> 00:44:58,747
defers ultimately to a text
editor for you to write your code.

932
00:44:58,747 --> 00:45:00,830
But you can set it up to
use anything you want to,

933
00:45:00,830 --> 00:45:03,980
whether that's VS Code or Sublime
Text or the like-- even Text Edit,

934
00:45:03,980 --> 00:45:06,010
if you are so inclined.

935
00:45:06,010 --> 00:45:09,865
SPEAKER: And prior to that, also from
Peter, "Love 2D has been updated.

936
00:45:09,865 --> 00:45:11,990
The distro in the course,
this is an older version.

937
00:45:11,990 --> 00:45:13,820
[INAUDIBLE] update with the course plan?

938
00:45:13,820 --> 00:45:15,070
COLTON OGDEN: That is correct.

939
00:45:15,070 --> 00:45:18,188
Yeah, the current distro that
we are using is for 0.10.2,

940
00:45:18,188 --> 00:45:19,730
which is mentioned in the assignment.

941
00:45:19,730 --> 00:45:22,580
Although we will be making an
update to the upcoming semester

942
00:45:22,580 --> 00:45:25,430
that makes it compatible
with 11.3, which

943
00:45:25,430 --> 00:45:29,900
is just a series of essentially copy
and paste across all of the source code.

944
00:45:29,900 --> 00:45:33,245
SPEAKER: And Ty asked, "Are you planning
to teach programming in Minecraft?"

945
00:45:33,245 --> 00:45:34,870
COLTON OGDEN: Programming in Minecraft?

946
00:45:34,870 --> 00:45:36,827
You know, that would be fun.

947
00:45:36,827 --> 00:45:39,410
I am personally a fan of Minecraft
and all of the crazy things

948
00:45:39,410 --> 00:45:41,150
you can do in Minecraft.

949
00:45:41,150 --> 00:45:43,380
You can use-- you can
do it the crazy way,

950
00:45:43,380 --> 00:45:45,172
which is where you
actually build computers

951
00:45:45,172 --> 00:45:48,790
using redstone or using electricity
or electrically modeled blocks.

952
00:45:48,790 --> 00:45:50,990
And that will take you a
tremendously long time.

953
00:45:50,990 --> 00:45:54,702
Or you can do it through something
like ComputerCraft or CC--

954
00:45:54,702 --> 00:45:56,510
I forget what it's named these days.

955
00:45:56,510 --> 00:45:59,450
But it's essentially-- it actually
does run, if I remember correctly,

956
00:45:59,450 --> 00:46:02,213
a Lua interpreter in one
of the blocks in Minecraft

957
00:46:02,213 --> 00:46:03,380
that is actually a computer.

958
00:46:03,380 --> 00:46:05,450
That lets you interact
with things in the game.

959
00:46:05,450 --> 00:46:06,980
So it actually is an
excellent way, I think,

960
00:46:06,980 --> 00:46:09,397
if you have the right environment
and the right exercises,

961
00:46:09,397 --> 00:46:10,640
for a student to learn.

962
00:46:10,640 --> 00:46:12,460
Haven't thought about using
it for CS50, but maybe it's

963
00:46:12,460 --> 00:46:13,520
something to think about.

964
00:46:13,520 --> 00:46:14,990
DAVID MALAN: And Joanna,
in answer to your question

965
00:46:14,990 --> 00:46:17,220
about using Scratch for
games, it's not something

966
00:46:17,220 --> 00:46:19,080
that we use in the games class.

967
00:46:19,080 --> 00:46:21,830
It's something that can certainly
be used in the technology class,

968
00:46:21,830 --> 00:46:24,270
for instance, or CS50 itself.

969
00:46:24,270 --> 00:46:26,440
And then Angela, your
question, "Is there

970
00:46:26,440 --> 00:46:29,498
a discussion about the violence and
illustration of women in games?"

971
00:46:29,498 --> 00:46:31,790
Not something that's covered
in this class, which takes

972
00:46:31,790 --> 00:46:33,350
a purely technical approach to it.

973
00:46:33,350 --> 00:46:35,058
But those would be
the kinds of materials

974
00:46:35,058 --> 00:46:38,240
that we're working toward building out
for more discussion-oriented classes,

975
00:46:38,240 --> 00:46:41,948
as teachers might use it in high
schools or college classrooms.

976
00:46:41,948 --> 00:46:43,240
COLTON OGDEN: Yeah, good point.

977
00:46:43,240 --> 00:46:46,120
And yeah, the course does
not have any of those topics.

978
00:46:46,120 --> 00:46:50,080
Also, I included all the games
that are very family-friendly.

979
00:46:50,080 --> 00:46:53,610
DAVID MALAN: All right, Brian,
should we turn the reins over to you?

980
00:46:53,610 --> 00:46:55,910
BRIAN YU: All right, thanks, Colton.

981
00:46:55,910 --> 00:47:00,000
So the final two classes
that we'll be talking about--

982
00:47:00,000 --> 00:47:02,990
one is about web programming, and
one is about artificial intelligence.

983
00:47:02,990 --> 00:47:07,220
Both of these classes are designed
to be taken after students

984
00:47:07,220 --> 00:47:10,340
already have the prior
experience from CS50 itself.

985
00:47:10,340 --> 00:47:13,968
These classes build on top of
CS50 and explore a little bit

986
00:47:13,968 --> 00:47:16,010
further what you can do
with programming and what

987
00:47:16,010 --> 00:47:17,970
you can do with computer science.

988
00:47:17,970 --> 00:47:19,828
So just a whirlwind
tour of these classes.

989
00:47:19,828 --> 00:47:21,620
First up-- and it looks
like we'll probably

990
00:47:21,620 --> 00:47:24,530
go a couple minutes past 2 o'clock
Eastern, if that's all right.

991
00:47:24,530 --> 00:47:27,800
But we'll try not to go
too far over that time.

992
00:47:27,800 --> 00:47:30,020
But as for the web
programming class, the topics

993
00:47:30,020 --> 00:47:35,150
that we cover, we start by introducing
HTML and CSS in much the same way that

994
00:47:35,150 --> 00:47:37,970
CS50 itself does, but
also introducing some

995
00:47:37,970 --> 00:47:42,410
of the more recent features
of HTML with regards to video

996
00:47:42,410 --> 00:47:44,570
and with regards to handling
large amounts of data,

997
00:47:44,570 --> 00:47:48,380
just to make the process of building
websites a little bit easier.

998
00:47:48,380 --> 00:47:50,737
After that, we turn
our attention to Git,

999
00:47:50,737 --> 00:47:53,570
which we've mentioned a couple of
times now throughout the workshop.

1000
00:47:53,570 --> 00:47:56,930
Just a version control tool
popular across all of programming,

1001
00:47:56,930 --> 00:48:00,170
but web programming especially,
just for keeping track of changes

1002
00:48:00,170 --> 00:48:02,540
you might make to a web
application over time--

1003
00:48:02,540 --> 00:48:05,900
how to do that effectively and how
to be able to manage different parts

1004
00:48:05,900 --> 00:48:08,600
of the program at the same time.

1005
00:48:08,600 --> 00:48:11,720
After that, we introduce
students to Python in particular,

1006
00:48:11,720 --> 00:48:14,090
taking a look at the
Python data structures

1007
00:48:14,090 --> 00:48:17,300
that you can use in order to
represent information in programming,

1008
00:48:17,300 --> 00:48:20,780
taking a look at things like
lists and dictionaries and sets

1009
00:48:20,780 --> 00:48:24,230
and how you can write functions to
manipulate these data structures.

1010
00:48:24,230 --> 00:48:26,570
And then, in particular, in
the next part of the class,

1011
00:48:26,570 --> 00:48:29,690
we introduce a programming
framework called django.

1012
00:48:29,690 --> 00:48:32,750
So if you've taken CS50, you
might be familiar with Flask,

1013
00:48:32,750 --> 00:48:34,100
which is a web framework.

1014
00:48:34,100 --> 00:48:37,070
Django is a very similar
framework, but has--

1015
00:48:37,070 --> 00:48:40,170
it's a little more full-fledged,
has more features to it,

1016
00:48:40,170 --> 00:48:42,940
especially when it comes to
building web applications

1017
00:48:42,940 --> 00:48:46,175
that deal with storing
large amounts of data.

1018
00:48:46,175 --> 00:48:48,050
So when you're dealing
with applications that

1019
00:48:48,050 --> 00:48:51,140
have lots of users that have
accounts, where those accounts

1020
00:48:51,140 --> 00:48:53,810
are storing information,
django makes it very easy

1021
00:48:53,810 --> 00:48:56,030
just to set up a web
application so that you

1022
00:48:56,030 --> 00:48:58,730
can focus on the interesting
parts of building the web

1023
00:48:58,730 --> 00:49:03,740
application without worrying too
much about the underlying details

1024
00:49:03,740 --> 00:49:05,360
and implementations there.

1025
00:49:05,360 --> 00:49:09,320
No relation to the movie in
the name of this framework.

1026
00:49:09,320 --> 00:49:11,810
After that, we take a
look in particular at SQL

1027
00:49:11,810 --> 00:49:14,750
and how you can use SQL to be
able to build a database that

1028
00:49:14,750 --> 00:49:16,525
works with your web application.

1029
00:49:16,525 --> 00:49:18,650
And here, we talk about
the various different parts

1030
00:49:18,650 --> 00:49:22,430
that a web application might have--
the front end that the user sees,

1031
00:49:22,430 --> 00:49:26,240
some of the more controller code that
operates how the web application really

1032
00:49:26,240 --> 00:49:30,110
works, and then a database that web
application might be connected to.

1033
00:49:30,110 --> 00:49:32,240
And we explore some
of the tools and ways

1034
00:49:32,240 --> 00:49:37,050
that you can have web applications
that interact with those databases.

1035
00:49:37,050 --> 00:49:40,050
Following that, we introduce the
second of the programming languages

1036
00:49:40,050 --> 00:49:41,383
that are covered in the course--

1037
00:49:41,383 --> 00:49:42,060
JavaScript.

1038
00:49:42,060 --> 00:49:44,370
In particular, using
JavaScript to build user

1039
00:49:44,370 --> 00:49:47,830
interfaces-- so using
JavaScript on the client side.

1040
00:49:47,830 --> 00:49:50,650
In other words, running
inside the user's browser,

1041
00:49:50,650 --> 00:49:53,070
whether that's Chrome
or Safari or Firefox,

1042
00:49:53,070 --> 00:49:56,130
to be able to make web applications
a little bit more interactive so that

1043
00:49:56,130 --> 00:49:58,320
things happen when a
user clicks somewhere.

1044
00:49:58,320 --> 00:50:01,180
So that when a user gets a
new message, for example,

1045
00:50:01,180 --> 00:50:04,640
they might see a notification window
pop up, talking about some animations.

1046
00:50:04,640 --> 00:50:07,890
Things like infinite scroll-- if you're
scrolling through Twitter or your news

1047
00:50:07,890 --> 00:50:11,670
feed, you'll often see new data
appear as you continue to scroll.

1048
00:50:11,670 --> 00:50:13,980
We talk about some of those
implementation details

1049
00:50:13,980 --> 00:50:16,720
and how some of the modern web works.

1050
00:50:16,720 --> 00:50:18,930
And then after that, we go
into some best practices

1051
00:50:18,930 --> 00:50:23,460
for building web applications--
things like testing and CICD,

1052
00:50:23,460 --> 00:50:25,710
Continuous Integration
and Continuous Delivery,

1053
00:50:25,710 --> 00:50:29,610
which are ways of allowing it such
that when you're building your website

1054
00:50:29,610 --> 00:50:33,030
piece by piece, your web application
doesn't need to just update

1055
00:50:33,030 --> 00:50:34,980
once a month or once a year.

1056
00:50:34,980 --> 00:50:38,280
But you can continually update your
web application so that every time you

1057
00:50:38,280 --> 00:50:40,950
make small, little changes,
your web application

1058
00:50:40,950 --> 00:50:43,648
can update for all of
your users as well.

1059
00:50:43,648 --> 00:50:45,690
And then finally, we talk
about what might happen

1060
00:50:45,690 --> 00:50:47,710
as your web application starts to grow.

1061
00:50:47,710 --> 00:50:50,580
Talking about issues of
scalability and security,

1062
00:50:50,580 --> 00:50:54,060
thinking about when your web application
gets too big for just one web

1063
00:50:54,060 --> 00:50:56,250
server to be able to
handle all the users.

1064
00:50:56,250 --> 00:50:58,800
How might you scale that
up to have multiple servers

1065
00:50:58,800 --> 00:51:00,420
and balance between those?

1066
00:51:00,420 --> 00:51:02,700
And what are the security
implications of doing

1067
00:51:02,700 --> 00:51:06,660
that sort of thing and security
ideas that you have to be mindful of?

1068
00:51:06,660 --> 00:51:08,525
This is a very project-driven class.

1069
00:51:08,525 --> 00:51:11,400
So throughout the class, there are
various different web applications

1070
00:51:11,400 --> 00:51:12,990
that students create.

1071
00:51:12,990 --> 00:51:15,490
So they start by re-implementing
something like Google--

1072
00:51:15,490 --> 00:51:18,540
just a search engine where
people can type in something

1073
00:51:18,540 --> 00:51:20,400
and see a whole bunch of search results.

1074
00:51:20,400 --> 00:51:22,770
And each of the course
projects in this class

1075
00:51:22,770 --> 00:51:25,320
is modeled after a
popular web application

1076
00:51:25,320 --> 00:51:27,970
that students might have seen
or interacted with before

1077
00:51:27,970 --> 00:51:30,690
so that they get an opportunity
to try and better understand

1078
00:51:30,690 --> 00:51:33,850
how the web applications they
interact with really work.

1079
00:51:33,850 --> 00:51:36,330
So next up, they build a
wiki, sort of like Wikipedia,

1080
00:51:36,330 --> 00:51:39,450
where users can edit new
pages, create new pages,

1081
00:51:39,450 --> 00:51:43,920
and search for various different wiki
pages that might be on the internet.

1082
00:51:43,920 --> 00:51:46,200
After that, they build
an e-commerce website,

1083
00:51:46,200 --> 00:51:49,710
sort of like an Amazon or
an eBay, where students

1084
00:51:49,710 --> 00:51:54,120
can build a website where users can
log in, put up items for auction,

1085
00:51:54,120 --> 00:51:55,630
and bid on those listings.

1086
00:51:55,630 --> 00:51:58,950
And then the highest bidder wins
at the end of the auction period.

1087
00:51:58,950 --> 00:52:01,710
Then they implement a variant
of Gmail, where they effectively

1088
00:52:01,710 --> 00:52:05,820
build a mail client where you can have
an inbox of all your email messages.

1089
00:52:05,820 --> 00:52:09,210
And then you can send emails
and receive emails as well,

1090
00:52:09,210 --> 00:52:12,630
before finally building a social
network, effectively like Twitter

1091
00:52:12,630 --> 00:52:15,870
or Facebook or something like
that, where users can make posts

1092
00:52:15,870 --> 00:52:18,420
and comment on those posts
and heart other posts,

1093
00:52:18,420 --> 00:52:21,900
for example, just to get a sense for
the various different types of web

1094
00:52:21,900 --> 00:52:25,020
applications that are out
there and the types of things

1095
00:52:25,020 --> 00:52:26,910
that you can do with
those web applications.

1096
00:52:26,910 --> 00:52:28,740
And then at the end
of the course, we have

1097
00:52:28,740 --> 00:52:31,680
students build a final project of
their own choosing, where they just

1098
00:52:31,680 --> 00:52:34,407
pick some web application
they would like to create.

1099
00:52:34,407 --> 00:52:36,240
And we give them the
tools and the resources

1100
00:52:36,240 --> 00:52:40,320
to go and create that application, at a
database to it, add a front end to it,

1101
00:52:40,320 --> 00:52:44,090
and try to make it a little
bit more interactive.

1102
00:52:44,090 --> 00:52:48,800
So that, then, is a brief tour
of the web application course.

1103
00:52:48,800 --> 00:52:52,070
The question is, how long
is each of the courses?

1104
00:52:52,070 --> 00:52:54,800
Generally speaking, the courses
are designed at Harvard to take

1105
00:52:54,800 --> 00:52:58,200
a semester-- so something
like 12 weeks' worth of time.

1106
00:52:58,200 --> 00:53:01,130
But certainly, they can be
adapted to work at other paces.

1107
00:53:01,130 --> 00:53:05,450
So often, even though CS50 and the
web programming class and the AI class

1108
00:53:05,450 --> 00:53:07,820
are all designed to take a
semester here at Harvard,

1109
00:53:07,820 --> 00:53:10,550
I know that oftentimes
for CS50 in particular,

1110
00:53:10,550 --> 00:53:14,940
you might stretch that out to cover one
year or even two years, potentially.

1111
00:53:14,940 --> 00:53:17,780
And so that can make things a
little bit more manageable--

1112
00:53:17,780 --> 00:53:20,810
the pacing is a little more easily.

1113
00:53:20,810 --> 00:53:22,820
Are tools like submit50
used in these courses?

1114
00:53:22,820 --> 00:53:25,280
Yes, you can use submit50
with these courses

1115
00:53:25,280 --> 00:53:29,090
as well for submitting work
and collecting that work.

1116
00:53:29,090 --> 00:53:32,000
Where are the databases
and the website hosted?

1117
00:53:32,000 --> 00:53:34,040
Ultimately, there are
multiple possibilities,

1118
00:53:34,040 --> 00:53:36,320
though the popular one
that we recommend is

1119
00:53:36,320 --> 00:53:39,050
a service called Heroku,
which just happens to be

1120
00:53:39,050 --> 00:53:40,940
one of the easier services to set up.

1121
00:53:40,940 --> 00:53:44,570
You can set it up for free, just to
take a web application and a database

1122
00:53:44,570 --> 00:53:45,868
and put that online.

1123
00:53:45,868 --> 00:53:48,410
But there are other options
available, and we talk about some

1124
00:53:48,410 --> 00:53:52,190
of those in the web
programming class, too.

1125
00:53:52,190 --> 00:53:56,452
We don't talk about Firebase, though
we do talk about other libraries.

1126
00:53:56,452 --> 00:53:58,910
In particular, this version of
the class talks a little bit

1127
00:53:58,910 --> 00:54:03,020
about React for front-end development
and for designing interactive user

1128
00:54:03,020 --> 00:54:04,150
interfaces as well.

1129
00:54:04,150 --> 00:54:07,212


1130
00:54:07,212 --> 00:54:08,920
All right, and with
the last few minutes,

1131
00:54:08,920 --> 00:54:12,750
I'll just go ahead and talk about
CS50's Artificial Intelligence

1132
00:54:12,750 --> 00:54:18,042
with Python, CS50AI, another course
that's designed to be taken after CS50.

1133
00:54:18,042 --> 00:54:20,250
And the important thing that
I'd like to mention here

1134
00:54:20,250 --> 00:54:23,310
is that while most artificial
intelligence courses, if you find them

1135
00:54:23,310 --> 00:54:26,850
online, require a fair amount
of mathematical sophistication

1136
00:54:26,850 --> 00:54:29,430
and background-- require
knowledge of calculus,

1137
00:54:29,430 --> 00:54:31,860
require knowledge of linear
algebra, which is involved

1138
00:54:31,860 --> 00:54:33,960
in a lot of artificial intelligence.

1139
00:54:33,960 --> 00:54:36,150
We made the intentional
decision in this class

1140
00:54:36,150 --> 00:54:40,170
to create an introductory artificial
intelligence class that doesn't

1141
00:54:40,170 --> 00:54:41,850
require that mathematical background.

1142
00:54:41,850 --> 00:54:44,910
So there's no need to know
calculus or linear algebra

1143
00:54:44,910 --> 00:54:47,160
to be able to go through the
curriculum in this class.

1144
00:54:47,160 --> 00:54:50,070
The prerequisite really is
prior experience programming

1145
00:54:50,070 --> 00:54:52,020
in Python, which is
assumed for the class.

1146
00:54:52,020 --> 00:54:54,150
But we introduce the
mathematical details.

1147
00:54:54,150 --> 00:54:55,590
There is some math we talk about.

1148
00:54:55,590 --> 00:54:57,720
We talk a little bit about formal logic.

1149
00:54:57,720 --> 00:55:00,420
We talk a little bit about
probability and statistics.

1150
00:55:00,420 --> 00:55:02,550
But we introduce those
ideas in the class,

1151
00:55:02,550 --> 00:55:07,350
and we don't assume any higher level
math that other artificial intelligence

1152
00:55:07,350 --> 00:55:09,270
classes you might see do.

1153
00:55:09,270 --> 00:55:13,440
So the topics we talk about are, first,
how to search for answers to problems.

1154
00:55:13,440 --> 00:55:14,590
How does AI do that?

1155
00:55:14,590 --> 00:55:17,140
How does it look for
how to win in a game,

1156
00:55:17,140 --> 00:55:20,360
for example, considering all
the possibilities in that game?

1157
00:55:20,360 --> 00:55:22,110
Then we turn our
attention to the question

1158
00:55:22,110 --> 00:55:25,410
of how it is that artificial
intelligence can represent knowledge.

1159
00:55:25,410 --> 00:55:27,540
How can AI store information?

1160
00:55:27,540 --> 00:55:30,330
And how can artificial
intelligence use that information

1161
00:55:30,330 --> 00:55:32,020
to draw new conclusions?

1162
00:55:32,020 --> 00:55:34,740
So we talk about things that
AI can be certain about.

1163
00:55:34,740 --> 00:55:37,660
But we also talk about things
that AI can be uncertain about.

1164
00:55:37,660 --> 00:55:41,670
If artificial intelligence might
know something with some probability,

1165
00:55:41,670 --> 00:55:44,940
but not be entirely sure, how
does it deal with uncertain events

1166
00:55:44,940 --> 00:55:46,950
and trying to deal with that?

1167
00:55:46,950 --> 00:55:49,110
We then turn our
attention to optimization.

1168
00:55:49,110 --> 00:55:51,850
So if there are many possible
ways to solve a problem,

1169
00:55:51,850 --> 00:55:53,690
how can our AI find the best solution?

1170
00:55:53,690 --> 00:55:55,732
If there are many possible ways to--

1171
00:55:55,732 --> 00:55:58,690
this is useful for things like if
you're planning a city, for example--

1172
00:55:58,690 --> 00:56:00,780
trying to plan where
the hospitals should be.

1173
00:56:00,780 --> 00:56:03,620
How do you optimally
place the hospitals,

1174
00:56:03,620 --> 00:56:05,940
so they're in a useful
and practical location?

1175
00:56:05,940 --> 00:56:08,523
These are the sorts of problems
that we try to take a look at.

1176
00:56:08,523 --> 00:56:10,232
And then in the latter
half of the class,

1177
00:56:10,232 --> 00:56:12,040
we turn our attention
to machine learning.

1178
00:56:12,040 --> 00:56:14,100
So we talk about machine
learning, what it is.

1179
00:56:14,100 --> 00:56:16,142
What are the different
types of machine learning,

1180
00:56:16,142 --> 00:56:19,360
the different types of problems you
can solve using machine learning?

1181
00:56:19,360 --> 00:56:22,110
And in particular, talking about
the sorts of tools that are often

1182
00:56:22,110 --> 00:56:24,960
used in machine learning, in
particular focusing on things

1183
00:56:24,960 --> 00:56:27,690
like neural networks, a very
popular model in machine

1184
00:56:27,690 --> 00:56:31,410
learning where you try and design an
AI system that's modeled on the way

1185
00:56:31,410 --> 00:56:33,300
the human brain works,
with these neurons

1186
00:56:33,300 --> 00:56:35,850
that are interconnected and
connect to each other in order

1187
00:56:35,850 --> 00:56:37,980
to try to draw conclusions.

1188
00:56:37,980 --> 00:56:41,490
And then finally in the class, we turn
our attention to natural language,

1189
00:56:41,490 --> 00:56:44,400
thinking about how do we
get artificial intelligence

1190
00:56:44,400 --> 00:56:45,870
to speak the language of humans?

1191
00:56:45,870 --> 00:56:47,640
To be able to understand our language?

1192
00:56:47,640 --> 00:56:49,950
To be able to respond to our questions?

1193
00:56:49,950 --> 00:56:54,360
And how things like Siri and Alexa and
other voice assistants on your phone

1194
00:56:54,360 --> 00:56:56,340
or on your computers might work.

1195
00:56:56,340 --> 00:56:59,040
In the process, we introduce
students to a number of tools.

1196
00:56:59,040 --> 00:57:01,207
Of course, the Python
programming language, which we

1197
00:57:01,207 --> 00:57:03,000
use for the entirety of the course.

1198
00:57:03,000 --> 00:57:05,550
But also, introduce them
to some common Python

1199
00:57:05,550 --> 00:57:08,350
libraries that are used for
things like machine learning,

1200
00:57:08,350 --> 00:57:12,120
such as scikit-learn, a popular
Python library for machine learning,

1201
00:57:12,120 --> 00:57:15,650
as well as TensorFlow, a popular
library for building neural networks.

1202
00:57:15,650 --> 00:57:17,400
And the advantage of
this is that students

1203
00:57:17,400 --> 00:57:19,890
get an opportunity to build
their own neural networks

1204
00:57:19,890 --> 00:57:23,300
without needing to implement all of
the math behind the neural network.

1205
00:57:23,300 --> 00:57:25,050
That normally, to
build a neural network,

1206
00:57:25,050 --> 00:57:28,880
there is a lot of linear algebra
and optimization involved.

1207
00:57:28,880 --> 00:57:31,350
And here, students can really
just focus on the problem

1208
00:57:31,350 --> 00:57:33,240
that they're trying to
solve, without having

1209
00:57:33,240 --> 00:57:37,260
to get too deep into the mathematical
details that are underlying it.

1210
00:57:37,260 --> 00:57:41,010
So just to give a taste for some of
the projects that students complete,

1211
00:57:41,010 --> 00:57:42,810
they start by building a game engine.

1212
00:57:42,810 --> 00:57:45,450
We have them build a tic-tac-toe
player so that they can

1213
00:57:45,450 --> 00:57:47,012
play against the tic-tac-toe player.

1214
00:57:47,012 --> 00:57:48,720
And ideally, they
should be able to build

1215
00:57:48,720 --> 00:57:50,640
a tic-tac-toe program that never loses.

1216
00:57:50,640 --> 00:57:52,950
It should either win,
or it should be a draw.

1217
00:57:52,950 --> 00:57:55,530
But the tic-tac-toe
player should never lose.

1218
00:57:55,530 --> 00:57:58,200
We then introduce some
logic-based thinking,

1219
00:57:58,200 --> 00:58:01,320
trying to build an AI that can
play a game like Minesweeper

1220
00:58:01,320 --> 00:58:04,110
to try and logic their way
through where the mines might be

1221
00:58:04,110 --> 00:58:07,560
and which cells might be safe, if
you're familiar with that game.

1222
00:58:07,560 --> 00:58:10,410
Then we have the AI do some
things that are more creative--

1223
00:58:10,410 --> 00:58:14,010
have students build AIs that write
a crossword puzzle, for example,

1224
00:58:14,010 --> 00:58:16,560
to be able to fill in words
into the appropriate places

1225
00:58:16,560 --> 00:58:18,328
and to try to do so effectively.

1226
00:58:18,328 --> 00:58:20,370
And then when we turn
things to machine learning,

1227
00:58:20,370 --> 00:58:22,020
things get even more interesting.

1228
00:58:22,020 --> 00:58:25,050
And we have students think about
self-driving cars and the implications

1229
00:58:25,050 --> 00:58:26,700
of those and what might go wrong.

1230
00:58:26,700 --> 00:58:30,330
In particular, asking students to build
just a small part of self-driving car

1231
00:58:30,330 --> 00:58:33,480
software-- building software
that can look at a street sign

1232
00:58:33,480 --> 00:58:36,450
and identify what kind of sign
it is based on the street sign.

1233
00:58:36,450 --> 00:58:39,990
So learning to look at an image
and try and learn from that image

1234
00:58:39,990 --> 00:58:43,150
to figure out what that image might be.

1235
00:58:43,150 --> 00:58:45,870
So that was just a
whirlwind tour of what's

1236
00:58:45,870 --> 00:58:48,472
covered in the artificial
intelligence curriculum.

1237
00:58:48,472 --> 00:58:51,180
But in short, we use Python
throughout the entirety of the course

1238
00:58:51,180 --> 00:58:54,230
to try and build these
artificial intelligence systems.

1239
00:58:54,230 --> 00:58:55,980
With all of the projects,
we give students

1240
00:58:55,980 --> 00:58:57,630
a fair amount of distribution code.

1241
00:58:57,630 --> 00:58:59,550
So they're not building
the entirety of the project

1242
00:58:59,550 --> 00:59:01,258
from scratch, which
might be quite a lot.

1243
00:59:01,258 --> 00:59:03,770
But usually, we give them the
framework and the structure,

1244
00:59:03,770 --> 00:59:06,870
where students are then adding in the
functionality and the capabilities

1245
00:59:06,870 --> 00:59:12,200
into the program to make the program
a little bit more intelligent.

1246
00:59:12,200 --> 00:59:15,230
So I'll pause now, if there are any
questions about the web programming

1247
00:59:15,230 --> 00:59:19,010
class, the artificial intelligence
class, or really, any of the classes,

1248
00:59:19,010 --> 00:59:21,947
now, as we get ready to
wrap up this session.

1249
00:59:21,947 --> 00:59:23,780
DAVID MALAN: Brian,
Bret asks, "I understand

1250
00:59:23,780 --> 00:59:26,687
the AI program is intended
to occur after CS50X,

1251
00:59:26,687 --> 00:59:29,270
but would it be possible for
students to go through the topics

1252
00:59:29,270 --> 00:59:31,115
without that background?"

1253
00:59:31,115 --> 00:59:32,240
BRIAN YU: Potentially, yes.

1254
00:59:32,240 --> 00:59:34,760
So the projects all
require Python and will

1255
00:59:34,760 --> 00:59:37,310
expect that students are
writing programs in Python

1256
00:59:37,310 --> 00:59:40,160
but the lecture is material
is all designed such

1257
00:59:40,160 --> 00:59:42,320
that you don't necessarily
even need to know

1258
00:59:42,320 --> 00:59:44,450
how to program to be able
to watch the lectures

1259
00:59:44,450 --> 00:59:47,425
and just get an understanding
for how it is that this AI works.

1260
00:59:47,425 --> 00:59:49,550
So I could see multiple
different approaches, here.

1261
00:59:49,550 --> 00:59:51,950
You could use the
curriculum as just a way

1262
00:59:51,950 --> 00:59:54,720
of introducing the principles
of artificial intelligence--

1263
00:59:54,720 --> 00:59:58,478
what machine learning is, how some
of these artificial intelligence

1264
00:59:58,478 --> 01:00:00,770
things that you encounter in
the real world might work,

1265
01:00:00,770 --> 01:00:03,590
without having students
actually get into implementing

1266
01:00:03,590 --> 01:00:04,720
the AI for themselves.

1267
01:00:04,720 --> 01:00:06,470
But for students who
are a little bit more

1268
01:00:06,470 --> 01:00:09,050
advanced, who might have a bit
more programming experience,

1269
01:00:09,050 --> 01:00:12,680
we do have these projects available
just to allow students the opportunity

1270
01:00:12,680 --> 01:00:16,613
to create AI of their own,
if they would like to.

1271
01:00:16,613 --> 01:00:17,780
DAVID MALAN: And Glen, ask--

1272
01:00:17,780 --> 01:00:19,020
he has a similar question.

1273
01:00:19,020 --> 01:00:22,370
"Is it possible to run
one of those classes--

1274
01:00:22,370 --> 01:00:25,460
web AI, game dev-- as
a quick intro, and then

1275
01:00:25,460 --> 01:00:29,330
maybe cover fewer projects
to make up the difference?"

1276
01:00:29,330 --> 01:00:31,350
BRIAN YU: Yeah, absolutely for both--

1277
01:00:31,350 --> 01:00:33,470
for, actually, all of
the follow-on courses,

1278
01:00:33,470 --> 01:00:36,770
really, they're very much divided
into different topics, such

1279
01:00:36,770 --> 01:00:39,770
that it is possible to pick and
choose certain topics that you'd

1280
01:00:39,770 --> 01:00:43,098
like to talk about without using
the entirety of the curriculum.

1281
01:00:43,098 --> 01:00:45,890
So certainly, all of the curriculum
is available as OpenCourseWare.

1282
01:00:45,890 --> 01:00:48,170
But you can pick and choose
what you like and adapt

1283
01:00:48,170 --> 01:00:51,650
the course in the curriculum
for your own liking as well.

1284
01:00:51,650 --> 01:00:53,922
DAVID MALAN: And John asks,
"Any words about CS50M?"

1285
01:00:53,922 --> 01:00:56,630
which is a mobile app development
course that a colleague of ours

1286
01:00:56,630 --> 01:00:58,040
taught a couple of years back.

1287
01:00:58,040 --> 01:01:00,740
We're probably not planning
to bring that back too soon.

1288
01:01:00,740 --> 01:01:02,780
That material, more so
than any of the classes,

1289
01:01:02,780 --> 01:01:06,530
has drifted out of date the fastest by
nature of the tech industry evolving

1290
01:01:06,530 --> 01:01:07,670
so quickly.

1291
01:01:07,670 --> 01:01:09,920
There's also more
challenging issues of access

1292
01:01:09,920 --> 01:01:15,380
to hardware for that class for students,
or requiring that certain software be

1293
01:01:15,380 --> 01:01:19,520
installed, which is not necessarily
within the grasp of teachers

1294
01:01:19,520 --> 01:01:21,500
with system administrators and schools.

1295
01:01:21,500 --> 01:01:24,080
So it's probably not
coming back too soon.

1296
01:01:24,080 --> 01:01:27,150
But we have not ruled it out entirely.

1297
01:01:27,150 --> 01:01:29,942


1298
01:01:29,942 --> 01:01:32,400
Gloria asks, "Are there any
promotional materials that show

1299
01:01:32,400 --> 01:01:34,890
sequences and course descriptions?"

1300
01:01:34,890 --> 01:01:37,740
We do have introductory videos
for each of the classes.

1301
01:01:37,740 --> 01:01:40,090
We will share those out
via email, if we may.

1302
01:01:40,090 --> 01:01:42,090
They're also on all of
the OpenCourseWare sites.

1303
01:01:42,090 --> 01:01:46,115
So I'll probably send
over those URLs as well.

1304
01:01:46,115 --> 01:01:48,490
All right, well, I think we're
indeed running a bit late.

1305
01:01:48,490 --> 01:01:49,370
My apologies.

1306
01:01:49,370 --> 01:01:52,820
But coming up next in just under
an hour will be our final session

1307
01:01:52,820 --> 01:01:53,720
all together--

1308
01:01:53,720 --> 01:01:57,860
Teachers Teaching CS50,
with Margaret, with Jenny,

1309
01:01:57,860 --> 01:02:00,800
and Douglas, all teachers
themselves, moderated by Jason.

1310
01:02:00,800 --> 01:02:05,540
And we'll use that time for Q&A as well
for some final connections and closure.

1311
01:02:05,540 --> 01:02:08,312
And then we'll be sure to stay
in touch in the days to come.

1312
01:02:08,312 --> 01:02:10,520
So why don't we go ahead
and officially adjourn here?

1313
01:02:10,520 --> 01:02:11,750
Please feel free to stick around.

1314
01:02:11,750 --> 01:02:13,670
We'll turn on some music
if you'd like to ask

1315
01:02:13,670 --> 01:02:15,240
us questions or chat with each other.

1316
01:02:15,240 --> 01:02:17,480
But we'll resume at 3:00 PM Eastern.

1317
01:02:17,480 --> 01:02:19,870
Thank you to Colton and Brian.

1318
01:02:19,870 --> 01:02:21,000