DAVID MALAN: All right.

This is CS50, and this is week 11.

Our very last.

And yet, curiously somehow, our second.

But it's great to see everyone here again,

and the goal today is several fold.

Among the goals for today, is to introduce you

to applications of computer science in the real world

by way of virtual reality.

And we'll do that by way of CS50 itself, a bit of gaming,

as well as by the world of archaeology-- something

that I myself took an interest in back in grad school--

and also we'll get, hopefully, a bit of emotional closure.

Indeed, if you think back on what we've been doing this whole semester,

whether you took some CS class before this or not-- I mean,

this class is entirely about problem solving.

And the thing I would encourage you to keep in mind

is that, no matter how cryptic C might have felt,

or no matter how you might have struggled with Flask, or Python,

or any other particular implementation details of problem sets,

at the end of the day, everything we did really boils down to this mental model.

And so truly if you walk away with nothing else from CS50 other

than this appreciation, that even though you might not necessarily

know in advance what goes inside that box, algorithms are the solution.

I mean most everything we humans do, with or without computers,

can be reduced to this form of problem solving.

And realize, too, that just 12 weeks ago, 73% of you

had never taken a CS course before.

And then you went through in Scratch, and then C, and then memory management,

and then implement your own hash table, or try

in your own web based application, and soon your own final project.

So I dare say that no one here is among those less comfortable anymore.

Indeed what ultimately matters now is not

so much where you end up relative to your classmates,

but where you all end up today, in this week 11,

relative to where you were in week 0.

Indeed, it's worth noting that most of the course's teaching

Fellows in course assistance, were exactly where you were, just a year ago

today.

Indeed, I thought we would hit play on a short film

that the staff has put together to paint the picture of exactly what it's

been like for them, since graduating from CS50.

I give you CS50 staff, for Fall 2016.

[VIDEO PLAYBACK]

- I'm Analea, and this is CS50.

[MUSIC PLAYING]

- Thank you so much to this year's staff,

without whom the course really wouldn't be what it ultimately is for students.

Indeed, more than just videos, and problem sets,

and tests, and quizzes, CS50 really is about the interpersonal experience,

that students have in the course, and that connection that they

make with the whole teaching staff.

- So as a student, I really struggled to learn pointers, but I had great TF,

and he was just so inspiring that I really wanted to join the team myself.

- When I applied to Yale, I was an English

to sociology prospective double major, and now I am a computer science major.

So that's a little bit about how much CS50 changed me.

- You can come in, take the class, do well,

and even know the material so well that you're teaching the next year.

- CS50 is one of the best opportunities you're

going to have here, while you're and undergraduate,

to teach a course to your peers, and to really be a leader amongst peers.

- When you teach something, you're able to gain like 10 times as much knowledge

as when you just learn it.

- I've become much more comfortable with computer science fundamentals,

just by teaching them, rather than taking classes on them.

- It's really amazing to watch these incredibly bright eyed, incredibly

enthusiastic, just fresh out of high school students, learning about CS,

and asking these really intense, really detailed questions.

Just getting really excited about the material with me.

- It's for that aha moment, when you're helping a student in office hours,

and they've been struggling for hours, and all of a sudden they get it.

And it's that moment that I think is really special.

- We are super, super excited every year when

we have new people apply for CAs, NTFs, and greeters.

And being on staff is the most fun part of CS50,

it's been super, super, defining of my whole experience at Harvard.

- To my students, I'd like to say--

- You're live!

- --I love you all.

- You guys are great.

- --And comment your code.

- You should be a TF or CS50 to be able to empower others,

it's as simple as that.

[MUSIC PLAYING]

[END PLAYBACK]

DAVID MALAN: Allow me to take a moment now, to thank a number of members

of the teaching staff, among them Maria and Walter, Doug and Alec,

Rob, Zamyla, and truly, CS50s whole team.

In fact, if you've never actually clicked

on the staff link on CS50's page, thanks to Luke in the production team,

you'll actually see the biggest abuse of animated GIFs ever.

But it brings to life the entirety of CS50's team here,

and so thank you so much to the entirety of our staff, our teaching

fellows, course assistants, producers, everyone here in Sanders

who's been helping us out all term, and everyone who's been helping us

out even before this term.

In fact, one of the most frequently asked questions at CS50 lunches,

or whenever I've chatted with folks one on one,

has been essentially along the lines of, and we just

got this question today, what's with the weird black and white dramas

at the end of lectures.

And indeed, if you haven't noticed, at the end of most

every lecture is a little vignette inspired, in fact,

by Citizen Kane, a film that you may have seen.

And even if not, it's meant to, when watched contiguously,

to tell a CS50 variants of that same story.

And even if you haven't watched them all, they're all on CS50's home page,

and we thought we'd give you a bit of emotional closure

with the last such scene, wherein it is revealed what Rosebud is.

[VIDEO PLAYBACK]

[MUSIC PLAYING]

[END PLAYBACK]

DAVID MALAN: So, if you have no idea what it is you just watched,

that's fine.

Take a look at CS50's home page, where all of them

are now concatenated together.

What you may have noticed, either from our first week's lecture,

or from some of the videos that have been

going online over the course of the term,

is that there's been this thing here.

This special camera that has eight lenses on it.

Because for the first time this year, we thought

we would try to push the envelope a bit technologically,

bringing into the classroom a new form of technology that you've perhaps

seen gaining steam in gaming, and in industry more generally,

virtual reality, or VR.

Which is a technology that allows a human to either, in simplest form,

take their mobile phone, and pull up Facebook or YouTube or the like,

and sort see around them the entirety of some three dimensional space,

just through the lens of that rectangular region.

But better yet, if you actually put on a special headset,

like Google Cardboard, or Samsung Gear, or Oculus Rift, or HTC Vive, or bunches

of others, you can actually transport yourself

virtually to a space like that.

So if you've been wondering what it's been like to sit-in

on lectures all year round in Sanders, you can actually go back

and relive that experience, thanks to this kind of camera here.

And in fact I can draw attention to it in the photograph here,

and I can also draw attention to CS50's Conor Doyle, a sophomore who joined us

just over a year ago on CS50's team.

In fact we met him at [INAUDIBLE] and he came up,

as pre-frosh are want to do, expressing an interest in getting

involved in CS50 goings on, since he's been

an aspiring filmmaker and technophile.

And so he actually joined CS50's team last year,

has been taking CS50 this semester, and has been our go

to guy for all things virtual reality, as well as

alongside CS50's home production team.

And so I thought it would be appropriate,

given how much time the team has spent on this technology, in large part,

not so much to simulate what it's like for Harvard students or Yale students

to experience classes in Sanders Theater,

but there's this whole outreach effort, these days, by way of a program

called AP CS Principles.

Which is a new AP course from the College Board,

that high school students around the world

can start taking in satisfaction of an AP credit.

And CS50 is just one of the implementations of that new course.

Co.org, UC Berkeley, and others have theirs.

And so really the overarching goal of this kind of technology,

is to give a window into a classroom, that high school

students, or adult students online, couldn't otherwise

participate in from such afar.

So allow me to invite up CS50's own Conor Doyle.

Welcome to Conor And while we get some things set up, would someone

like to volunteer to be a participant in CS50 VR,

putting on his or her face virtual reality goggles.

Can't quite see them, any faces with the lights, OK, right here, OK.

Come on down.

Wonderful.

Tiptoe past the camera, there we go.

All right.

Conor's getting things set up, and what's your name?

JONATHAN: Jonathan.

DAVID MALAN: Jonathan?

David, nice to meet you.

Come on over here.

And so if we put you center here, Conor, as we

get Jonathan set up here, what is it we are about to do, and what is it

he's about to experience?

CONOR DOYLE: Sure, so, the Nokia OZO camera has eight sensors on it,

and it's capturing the entire world.

So wherever you are on stage right now, it's capturing you.

And you can't really escape it.

So what we're doing, is we're taking the HTC Vibe, which

is a room scale VR experience, one of the best headsets on the market,

I think, right now.

And we're going to put it on you, I'm we're going to go back to week zero,

and you get relive sort of week zero experience, with this HTC Vibe headset.

DAVID MALAN: And so after each lecture what CS50's production team is

essentially this, it's a little washed out on the screen here,

but it's eight images from each of the lenses,

and then using special software, do they stitch it together in such a way

that the resulting image is essentially a video that's a full 360 degrees.

In fact, the reason it looks distorted here,

is because once you put the headset on, does

it wrap that world around your head, so that if Jonathan looks up,

down, left, or right, his eyes are actually

going to be seeing something a little different.

So we'll change the screen here to Conor, and Jonathan's set up.

So you are seeing now-- if we could perhaps

dim the lights-- what Jonathan is seeing on his own headset.

[VIDEO PLAYBACK]

[MUSIC PLAYING]

CONOR DOYLE: This is week zero.

- This is

[INTERPOSING VOICES]

- --introduction to the intellectual enterprises of computer science,

and the art of programming.

And my name is David Malan, and I was just thinking this morning,

that it's been, amazingly, 20 years today, since I last

sat where you guys do now.

DAVID MALAN: So you'll notice, too, it's a little hard

to see the touch screen from the headset so if Jonathan,

you'll look toward the screen, and then look down,

you'll see that it's digitally superimposed there,

so that for code especially, you can see it all the more realistically.

All right.

Well thank you to Jonathan.

Let me bring you back to reality if we can.

[END PLAYBACK]

DAVID MALAN: Thank you.