Uh huh. Uh, so the title of my
talk is code as a metaphor for computational thinking.
And I hope that during the course of the roughly
our that I'll get 20 both a little bit about
where I think computational city is going, what it
is and why code a good metaphor for it in
the hospital. So it turns out that when you
show PowerPoint slides off emissions that I distribution, you
can know people in the audience are reading into.
So our species music deserves a citizen with minds wide
away from your basic understanding of how the world works
and the world that I believe this is true.
And I think that the world today is very digital
. And so the understanding how the world works requires
understanding of how digital processes work. Yeah, approach
from a couple of years ago. We need a
data literate citizenship, not just a small elite package
, and policy wants. The best way to cultivate
that broad based literacy is not for these small in
different quantities, but the flood of this state.
But more than that, we also need to involve
educated to help provide support. You increase people's ability
to use up the more than its current. So
many of the initiatives that I'm involved with them going
to talk about our how to get everyone well versed
in computer science and computational system, not just the
people that are gonna be software engineer, but everybody
that's becoming a citizen. Whatever country living, although
I'm pretty us centers in my point. So where
are we going today? It turns out that it's
a good idea to tell you where we're going to
go, then go there and then tell you later
where we've been. You expect me to do that
? And so on the next in line, I'm
going to tell you some stories because I think that
one of the one of the grants I have about
problems is really about stories. And if I don't
tell you good stories, you're not going to take
away, uh, many things about competition. This
is how it works. Some of these stories are
personal, and those are great stories. Not everybody
has the same personal experience, So knowledge tell somebody
else's story dependent. Uh, there are some local
, regional and national initiatives I'm going to speak about
that. Are doing confrontational thinking. Some of those
are really done right here. It's getting tech as
part of the CSS 10-K and C a principal commissioners
. I'm going to talk about who is the audience
for this. So right now I'm addressing you.
But I'm addressing you, and some of you are
under graphic. Some of your graphic, please.
Faculty staff. But I'm also addressing you so that
you can go out and explain to your Congress person
or Barack Obama if you happen to be good friends
with him or the next president. United States,
whoever that might be if it's not, or your
friends and neighbors or your scientist friends or your heart
playing son, Whoever you might have that you have
to explain yourself and the code code is going to
turn out is a metaphor for all of this.
So I'm going to explain to you what I mean
by code, with several examples, and some of
them are gonna look unfamiliar, and some of them
are gonna look familiar now. So before, before
we start, how many of you know Morse code
Code cold. You know, Morse code cold.
Two, two. How many of you know what
this is the Morse code. For now, you
have to make an intelligent gift. It's not a
tricky I'm not trying to hide anything from you.
How many of you that don't know Morse code?
No. The Morse code for S O s.
So for some reason, people know the Morse code
. Sus Well, guess what the dash dash dash
is up there. That's the Oh, and given
that this slide says something at the top, I'm
guessing that if you can figure out what it stands
for, so that's code. And it turns out
that Morse code is an interesting coaches study no one
really uses anymore, except for him. Radio operators
. Are you a ham radio operator? And that's
why you know it. Okay, here's some more
code. They don't know what this is. The
code of Hammurabi. It's the code of Hammurabi.
A lot of people know that they don't know what
the code of Hammurabi is, but they know that
this is it. It is the code of Hammurabi
. Here's some code. Interestingly, these days these
are the area codes of Virginia. But most many
of you probably have phones that you've had for several
years that don't have area codes from because it turns
out especially for people in the mobile society. You
keep the phone number that you had when you first
got your mobile phone, so it's hard to know
where people are from anymore. I used to be
able to look at my phone to know who was
calling me. Oh, that's my friend. Double
booking. And here's more of the code that we're
going to look at today. And I'm borrowing an
idea from Lawrence Lessig, who writes about this kind
of code. There's East Coast code and there's West
Coast Code, the West Coast code of the Code
of Silicon Valley, and that's software. And I've
simplified that with Google and Apple. The East Coast
code is the code of law that happens to Washington
, D. C. So we see both these
kinds of code, and for me it's very important
that to make sure that I'm grounding the code I
speak about, which is often software in the world
and the world revolves around the code of law,
we don't get to live in just a virtual world
. We have to live in the real world and
understanding law turns out to be a good idea.
So I'm gonna give you some examples. But beforehand
, just a show of hands again. How many
of you have been to Google? How have you
been to apple? Cappuccino. How many have you
been to the Congress? More people have been.
We're not. We don't live that far away.
Okay, here's an East and West Coast code.
I'm gonna give you an example. You decide multiple
choice questions. Which code is which? Here's one
example. Uh, some of you can understand this
. It's written in a particular programming language and it
came from something real. You might even be able
to sell something kind of real. And for those
of you that understand, you might even be able
to get the realm from which the problem pain.
Based on some of the string constants that you see
that you might be able to. Here's some other
code. It turns out that code the code of
law, is code. There's the U. S
. Code that is the national code, the legal
system that's embodied. Here's some code about what mass
skills secondary school students should have. It's written into
the U s code and understand this interplay is how
I want to ground computational Think. When I was
getting ready for this talk, I turned out that
I found some new things. I found out about
the Code for America, which I never knew existed
before. In case you don't know I'm sharing.
It's like teach for America. But you go right
and we go write code to change how cities,
how urban landscapes and how the urban government is evolving
. It can be a fellow. It's not so
much for people that are just starting out for people
that are already established. But it's an interesting idea
. That code for America is basically putting together both
these pieces both the East Coast and West Coast.
Um, and now I'm stepping aside and giving you
a little information about my talk. Typically, at
least recently, some of you have been going to
job talk. I don't know how the job talks
here work. My guess is that candidates are very
similar to our candidates. First, they give you
this big overview that everybody can understand, and then
they start giving you some information that no one except
a few people in the room, understand? And
I hope that's not going to be the case for
me because I'm not auditioning for a job. But
I do want to tell you about engagement in didactic
. I brought a book with me, too.
This book is called Indiscreet Golf. Very clever.
Title carefully about, and you can get it online
using this website E books free download dot org.
If you go to that website and now see I
when I look around, the people that are under
the age of 25 are smiling. The other people
are not smart. I'm not sure you can see
all the pieces up here, but let me ask
you this question where it says right here. Premium
download regular down and down are those actually the buttons
you pressed to download this book? Yeah, the
answer is no, but only the people under 25
million all the rest of us old people go there
and press all these buttons. And then now where
it comes on a computer because the actual button to
download this illegal book because it's not legal to download
free books free download. It's a tiny little link
that you have to know how to find. And
apparently, once you're above a certain age, you
don't know that and below a certain age, you
do know that I don't know why. That's the
case in this book. At the end, this
mathematician who wrote this book says, Here's the deal
when you're giving a lecture, he wishes somebody told
them this when he was getting ready to be common
academic. Make one point. Make one point.
It can be a theme with variations, but don't
try to make 1000 points in one box. Don't
run over. People have someplace to go Even though
everything you say is wonderful, make sure you relate
to your audience. People like to hear about themselves
, So I try to make sure I do that
and give them something to take home. So I
hope I am going to take home. But in
my case, I could get Remember this to the
10th is about 24 mhm. And I'll tell you
a story about that later, too. Also,
the answer to any question can be it depends.
You remember that I have. This is my met
apartment. I'm gonna get back into my talk is
, it's a good idea to know this. This
is a book called Ideas and Information by Arno Penzias
, who won the Nobel Prize in physics Because you
want a Nobel Prize in physics. He knows he
must be smart. Exactly. He must be smart
. That's what everybody says. No one says Lucky
. We must be smart. So in this book
, he has a quote. I'm going to read
the story that he wrote about a friend of his
, another Nobel Prize winning physicist. They travel and
pumped with groups or something. And here's Arnold Penzias
. I'm going to just read this past my first
boss at Bell Labs. Is there someone else in
this room that worked at Bell Labs? Really?
It's interesting to see I'm connected to the Army.
Yeah, to go to work. My first boss
at Bell Labs from one of the smartest people I've
ever known comprised a terrible secret. He felt overrated
. As he spoke, I realized you should exactly
the same feeling I could really pick for me saying
the same thing about myself. People around you think
I'm smarter than I really am. You don't suspect
learn things more slowly than naked, and that's fundamentally
when I listened to a presentation on something new.
The only thing that keeps me from a very stupid
is not ask questions, things that others obviously already
understand. I know they understand it because they're not
asking any question. The things that I know about
are really easy to understand. Simple by comparison to
my colleagues. Areas of expertise. Um, all
right, so it's all good. I'm trying to
make sure that you understand from this from the first
voice question, I don't see you jump up.
Is there an alternative to the traditional introduction to computer
science? And I'm gonna give you a couple and
they're going to be involved in a computational thinking because
that's what I'm talking about computation. So if we're
going to have an alternative to the traditional production,
what did it look like? And here, a
couple of choices and I'm going to talk about two
of the and part of motivated, and I'm going
to mention one of them that just been spending some
time. One thing that we could change is what
you keep. So that's an initiative that I'm going
to talk a lot about. CS principles. That's
something that's happening here in effect as well as national
nationalist. And I'm going to talk about a course
that I teach what I call it Square. Does
the Internet Protocol meets intellectual property? Mhm. That's
going to become a CIA principle by court martial.
That's changing the content of what we do, and
another one you can do is you can change how
you can. You have high quality. Three course
is off to 200,000 people. Apparently, some people
think you think here is an example. This course
started last week. See us one on 11 on
one. That's the first course of computer science.
These gentlemen, we'll teach you fight on open in
70 At the end of seven weeks, you have
written a searching, which is a little different than
my course writing Python 15, and I would be
happy if it's at the end of 15 weeks my
students to solve a very small problem, much less
ambitious than violence. So I think to myself,
I'm doing something. Maybe my standards are fine,
but I'm not telling. But I am enrolled in
this sport, and I can tell you that after
a week since I already know Python as you get
. I'm not sure that if I didn't already know
Python, I would understand that they were talking about
. But it's an interesting model of education. I
think it's something that you're going to have to pay
attention to if you're not already. Is everything online
in the browser? All your code is written in
the browser. All your quizzes during the browser,
there's no other construction is kind of, um But
on the other hand, on the other hand,
I want you to remember this. Wow, this
is all new now. Some of you are old
enough not everyone to remember when filmstrips will use this
life. Here's how I know that. You know
, I just mortified. He Yeah, the only
old people now filmstrips they were going to revolutionize each
. So was telling television is gonna come to school
and revolutionized. So all these things apparently are gonna
revolution. Now there is a difference. The difference
is, well, maybe there's no you're going to
have to decide. But I want to remember that
for many, many years things are going to revolutionize
education, and some of them may actually succeed,
and some of them may not. But you should
understand these two different quotes and you can try to
figure out who said with one. Those who cannot
remember the past are condemned to repeat it. And
I don't know much about history. I don't know
much about biology. Don't know much about science talking
much about French actress. Yeah, uh huh.
Here's here's Here's this one and I want to relate
that to computational thinking because here's another quote about why
what we do should be both more about more than
Tober, but it better be grounded in focus.
English is not history. History is not science.
Science is not ours. Not music, art,
music or minor subjects. English history times A major
subject. A subject is something you take when you're
taking it, you've had it. And if you
had it, your immune and you have to get
right what you're doing here, What you're doing in
computer science should incorporate everything that your students know.
And ideally, it should be interdisciplinary to some extent
, because if all we're doing is the things that
we know how to do, we're not gonna be
able to address a huge variety of students that didn't
grow up knowing how close you take. And it
turns out that the students that grow up knowing how
to close that they were 10 are on there.
And now when I say all magnificent, there's a
whole huge group of huge and people that were failing
to address. If you don't have to broaden what
we look at and so we have to ask a
different question. Here are the questions that see US
educators like good stuff. It's and I have been
part of these conversations over and over mhm and in
fact, the CSCE principles. Of course I'm going
to talk about the first question. Is that the
first question that I'm asked when we talk about this
course now tell you about this person. What language
are you teaching? Are you teaching the kidnappers?
And it turns out that if all our conversations are
about tools and you know what the function give me
Yeah, mhm. I mean, we could go
for hours on this, it turns out, and
this is the wrong, unproductive hours to spend because
when you start having these conversations with people outside of
our field, and that's what they come to you
. They come to you with questions like I'm having
trouble with yourself. I know you're interested in this
because I keep hearing you talking about where So you
must know a lot about this because you don't really
know anything about it. So we need to change
what we're talking about. I want to change what
we talked about. I don't want to talk about
the fool I want us to change. What are
vernacular is the everyday language spoken by people as distinguishing
of literary right, the idiom of a particular trade
or profession. And I would like us in computer
science, especially compared to the agent, to change
what we talked so that we're talking about problems and
I want to use problems and make sure that that
that's what I would like that we need to talk
about this with each other so that when we go
and work with other academics and other professionals and policy
makers that were having similar conversations, and here's why
this is a good time to talk about a fundamental
understanding of computation and computational or algorithmic. Thinking is
increasingly important success in the digital age computing education will
benefit all feet, not just those interested in pursuing
computer science or information technology. Yeah, so we're
trying to make a case when I say we a
big group of people that many people to take computer
science, corporate, not just those who want the
software engineering degree or that want a job after that
proper. But we have to make sure that we
don't shortchange community property. So that's what we're going
to go in order to get there. We have
to explain complications, so I'll just make a kind
of building a small foundation. Almost. I'm going
to tell you what this is, and I'm gonna
contract to metaphors before I get back to code.
This code is it used to be in the old
days that people talk about computer science as a milky
. It's a medical school that stands on three with
the likes of engineering, mathematics and computer sciences.
Accomplice kind of the culmination of engineering, mathematics and
science, and you, too, could milk the
past. If you're oh, I think it would
be a better metaphor to take these three things,
which are parts of computer science, but instead of
having to be a milking school. Haven't been a
neural cute. Some of you have seen average.
If you see our, you'll know that not citizens
President Mhm have this cute that at the end,
as you could handle that, connect directly to your
brain and you can find dragon. Now that seems
way more treated, can use and looking. So
I would like to three different branches of engineering,
science and mathematics that I'll need you to sign this
bill to be intertwined, to be graded, not
three separate things we kept thinking. You have to
study the subject. I can't. They are all
interconnected. I have to study them all together,
and that's where code from. So I'm gonna get
code code. I'm gonna tell you that code stories
are gonna explain. So I'm gonna give you some
stories that are based on Oh, and they're rooted
in pop. So I want to talk about the
problems as a way of making sure this is where
we're going to understand occupational. And if it says
in the bottom left of my slides is intended to
describe computational thing. Cold is a network it needs
to run. I'm talking about code every month when
we talk about the West Coast code. That's fine
. But in the end were computer scientists, computer
programmers, software engineers, human computer interface experts.
We don't have running code, and I'm gonna call
that runs on a real machine. One on fruit
. Have one. Uh, wouldn't you? Mhm
. What combinations? In here. Here's the scores
. You can look at the polls and I'll give
you everything. This is something in the news.
I like to look in the news because you weren't
this mhm to 18 12. That was last week
. Last week this gentleman was acquitted, all right
? He was acquitted. He's only taken open source
code that he told himself this guy surveillance call it
says a year. A year ago, he was
convicted of stealing sources, convicted of sealed sources.
I wanted you to get to things that take away
from this one is. I hope you're noticing this
young student. How much would you pay at Goldman
Sachs to write code? You've got a usual sound
. Okay, A reasonable. And he was the
highest paid program of when he left Goldman because 400
k per year writing software that wasn't enough. You
got a competing offer dictating three times and then going
to the new company because as you want to take
all the cold and come up on the submissions,
he said, it was all open source code.
He was convicted of industrial espionage, espionage, and
they threw it out and they just threw it out
, saying, You know what? This is not
This is not a natural disaster, this guy,
Let's go And it's arguable whether it's open source code
, but you need to understand a couple things.
First, you need to understand if you're educated.
Sensory, what open source. He doesn't understand that
. I mean, I understand. I was like
, Oh, former are so that's going as the
story is in the news, all the complications,
computations. Here's a quote and I led into this
with my after that. This is a Supreme Court
case. How does not? Not today. Pensacola
defined the kind of material I understand being raped in
the industry, uh, our people completely, ever
since I could never succeed to impose their doing so
. But I know it sounds to you, and
it turns out that a lot of fewer does not
talk about Supreme Court cases, all taking sweet talking
about Supreme Court case involving or not, it couldn't
come up with a legal definition of pornography. How
many said was, I can't really define it,
but I know it was. And so I'm going
to argue that maybe we need to go that way
. Before we tried to find it with just a
few words, I'm going to give you some stories
and you're going to tell me, is this complication
of thinking and then I'll try to wrap it up
and say, Oh, yes, it is or
is not conscious Colonel up. So here we go
. This is a true story. A true story
. It happened about 1995. I was driving to
work. I listen to NPR. They gave a
public build, the latter some white by changing one
letter white wild whale shale. As I was driving
to work, I thought, You know what?
I can solve this optimal. I know about shortest
path problems, and I can write a program that
will connect all these nose in the graph and their
one apart facing the letter. And I think I
can do this. I can do this and I
got to my office and I called my brother.
That's my brother was an Englishman. I said,
Guess what? This puzzle came on. He said
, Okay, I'm gonna go to your computer scientist
. Let's go. An hour later, I had
written my program. I called him up and he
said, I have a lot and I said,
I have a lot My artist who agree Optimus and
my ladder I was 16. 16 words. White
House in 16 years My brother's It's mhm. My
was probably What is the difference? I guarantee you
I was off. Well, what did he have
that I didn't vocabulary. He had vocabulary. He
has this word. So I have never heard the
herself. Apparently it means kind of A as he
explained to me, the different sound that the wind
makes moves over the moors. Okay, It wasn't
in my dictionary. It wasn't in my online list
of words, so I added it to my online
list of words re around my program. Sport,
Please. My program was optimal. But if you
don't have the right input, it doesn't work out
. So to me, this was a competition taking
source because I was thinking computational. My brother wasn't
but together it was about being together that we solved
a different problem back then we had before. It's
not. That's my reading. Not gonna give you
three examples that are all related at all around about
code. I'm gonna give you the moors and pictures
. And I had an interesting quote from somebody that
some people record. Uh, this is the gentleman
. The major quote the halfway last year for this
year, John, Parking 1000 and one word is
worth more than a. I'm gonna give you both
pictures and work because that's typically not the way the
hotels and down here, I've got a graph that
turns out to be about computational thinking and big data
Not many of you probably have seen, but not
everyone has seen Google Engram. Google has digitized millions
and millions of books going back a long way.
And this is the graph of how often in all
the books that Google has digitized the words mathematics and
physics up here over time. Well, it's kind
of interesting. Those curves have the same shape.
I don't know what's going on with that, but
I think it's worth exploring if I had more time
. But here, my three problems, I'm gonna
give you three problems that are related, and we're
going to see wide about computational thinking and how they
actually work. Here's one problem. I found this
English online, and I looked it up. It
turns out, as you can see, this image
occurs 14 times in the entire Web. And if
you've never used China denies the facility that finds this
for you, and it scanned 2.9 million images in
point Oh, 47 seconds. That's pretty rapid from
the girl. How did it be? Okay,
I want to know, how did that and we're
going to get. But here's another problem that some
of you, some of you may have it.
Some of you have sound town. Can you have
chosen? It works similar. I could play a
song. You could stand in the back, hold
up your phone, and after listening to 20 seconds
of the song, it would tell you what that
song. And at least if you use sound hound
, you can hum this song and we'll tell you
what. How does it do that and why does
YouTube use that? And I'm gonna get you Jordan
how to do that. Here's the first story I'm
going to explain. And it's all related. That
ends about Coach. I needed to drive. I'm
confused. I was offered the flock, I figured
, probably taking 12 hours fly here. And three
hours ago I told you what mhm. I had
to get here. I got directions. I was
starting at a Chipotle, and I needed to get
here, and I took these directions. And this
is the U R l to hold those who held
those directions. And I want that. Remember that
. But that u r l is really wrong.
So I knew about some services that would help me
out. And now I was going to explain this
in power point, but to challenge myself for the
first time ever a good idea not to give it
off. It is familiar. So I'm going to
break some new ground for me. I'm going to
use another technique for explaining to me. I don't
know if any of you have seen Crazy and Mr
President. All right, well, apparently, I'm
gonna give my first present presentation to explain that problem
. This is an example of computational thinking. It's
already been a powerful. Here's the problem I was
trying to solve. I needed to get from the
Chipotle in Durham, North Carolina, by getting in
my car and driving to this pen breath. And
in order to do that, I was going to
use Google. Yeah, so there's my direction.
Hi. Got that? You are l and I
thought, what could you better with this information and
tweeted unfortunately for me and I found this out by
running my papers Command on two WC. It has
331 care. That's too big first. Yeah,
and I do have a quitter. So what do
I do? Ah. So there you are.
There are three. You are also interested. Some
of you know about these are computational thinking how to
best. How do they work? Let's try to
figure that out. There are three different ones that
resulted from those services. There's the Google one that
Google automatic gives you. There's a bit and I
actually have my own account so I can customize the
u R l So instead of being y o i
f j m, it was the e u that
made my entire day. And then I realized I
don't really know how they work. How do these
u r l stroking services work. So before I
give you the answer, does anybody have, like
, you can only say one word? Yeah,
they work by and you can give you or it
could be a sentence, but it better be a
very short time. So I'm looking for your answer
before I give you mine. The idea behind How
did you are? You explain it to your friends
and our computer scientists. More to the computer science
. One word anybody want to give me a work
is my idea. Redirection. That turns out to
be a great word. I'm gonna I'm gonna take
that work. What's another word? Map? That's
a little to date. You You go, you
go. Nothing. The big one was smaller.
Yeah. Are you not the big ones and small
ones? You don't tell me. I can tell
you, Nick. Nickname Major. Well, we
can put in this all day and I don't need
to map. Here's how I need to map.
I'm gonna show you how it works. It turns
out that there's my alphabet. It has 72 characters
, uppercase letters, lowercase letters and digits start at
62. I don't have How many different Urs are
there that are six characters long? This is part
of that mathematics. So most of you know that
means that there are 56 billion different accesses that I
can store. That's a lot more than 56 million
websites in the world. Are there more than 56
billion? U r l remember that you are.
All I got was from Google, with all the
parameters supported. Yeah, there are. Okay,
now, how does this how does this whole redirection
table? Here's what actually happened. And most when
I've asked this question before people come up with mapping
, they say hashing. I'm hashing at some smaller
things. But very few people know about the direction
. You must be a really well rounded cyber citizens
. So I applaud that here in this capture of
what happens when I made the connection, was this
redirect real one? How did you know about feel
? How did you know? About 404 How do
you see Eric? 44 Okay, well, those
two things are all about the web error. 44
and 31 Those are part of the http protocol who
made up and http. Protocol is like a t
M machine. I get well, I can't stop
the music. Who made it up? The idea
here. Who is the idea here? They make
up the protocols that make the Internet work. Who
was them in here in the idea? Could anybody
here that the idea? Yes, it's open to
everyone. If you want to be in it,
you just go. Yes, you can start participating
and you have to get to me. You can
just get online for free. It's open. It
takes forever to get something done mhm on a free
and completely open. It turns out there's another proof
that does this, and you should know these things
besides known about code. If you're going to understand
the Internet because the Internet isn't just about TCP and
I teamed with your both peace protocol, the peas
, the protocol. Okay, the idea and they
work together with the WBC, which is a global
consortium. Not everybody can be a member of who
invented the well. No, but what? That's
a good answer. And that's the answer everybody always
gives. But I invented the Internet. Okay,
which is very different in the Web, which is
incentivized. Who is Tim Berners Lee arguably invented the
Web. Alcor had a hand in Internet. So
that's my friend. Become presentation of competition. Okay
, just as I can say that I've used present
and I appreciate you want me to do that.
What's going on with that? There is a protocol
, and by examining each of these stories and more
detailed, I think you better understanding how code works
. That was the code of protocol, which is
related to the code of law you can't do.
You are shortening services without passion. You have to
be able to pass because you have to return an
arbitrary length string into something that's six letters long.
Okay, now the six letters. The letters are
very different, but that that's kind of bread and
butter and second courses of your sciences. And then
with that Eric 0301 you have to be able to
have their handshaking protocol do that. It's important to
understand that when you make a connection to a Web
page, it's not a miracle. Mm. Can
you see a page? Quickly? It's soft.
And software that's based on protocol that were designed by
anybody in the world that wants to him. That's
a very egalitarian system that's different than how a lot
of other systems work different than how the telephone system
works. For example, do you have to buy
a spectrum and the FCC to be able to get
? I'm gonna give you another example of my first
one where I took the Virginia Tech, remember,
single and looked it up. So I'm gonna give
you some more information about that by exploring it a
little more in depth because this is one of the
examples that we use in our first court and the
other groups are using in their principles. Course.
Finish up these principles. I want you to understand
where people So there's two kinds of explanations for that
. Then one is about stable sources, and one
is about steganography. Many of you know about state
of sorts, those interviews you know, when you
work for you know a lot about you forgot when
you have a kid you remember steganography used to be
that you would hide messages in people's hair and the
hair will grow over it. After that traffic on
the right, you can hide messages in the captain
Ted. So here's what I did. I took
too simple. Yeah, I took the hope.
The Boston mhm. Why did you okay? I
don't really understand the Blue Devils. Why is it
blue? And why you get done? Well,
these are the mascots that were stuffed with. And
what I want to explain to you is that if
you take one image and hide it in the other
, using stigma graphic techniques, you can explain this
about 10 lines of code. And then I want
to take the issue of the Internet and the Web
and scaling it to see why this might make a
difference. If you don't like images of athletic people
, you can take a really famous computer science example
without, you know, and you can take your
son. That's what I and he can hide one
image and the other. And then you can go
look this up. We'll explain what I'm talking.
I took the power depend on and took every RGB
values. And I took out the least two significant
businesses are g got. And then I took the
two most significant. It's my son, and I
stored them in the least significant bits. Okay,
that's all I did was I removed these low order
bits and I stuck in the Khyber and these are
actually the images. So you can see I put
this power coming on. I took my son and
I do this. Here's what happens when you extract
it so you can see the Paris Hanoi image pretty
much the same. My son sons images a little
. So when I looked it up, I got
the same answer This. It turns out that they're
not as many occurrences of this power grab it online
as there are of this blue that Yes. So
I took the original Blue Devil, And I used
to know tonight is the service that says it found
334 occurrences by looking two point oh, nine billion
images just in the sector. And then I hit
the Virginia Tech image inside, and I took that
image that now has both less and more information,
depending on how you want to look at it.
And I look that one up and had 337 results
, which is essentially the same because when you look
it up and get different answers each time, close
your mind. So whatever technique. 10 A.
This is a tonight. Whoa, whatever techniques institutions
looking up, I can hide information and still have
it. And it doesn't matter whether those images are
JPEG or PNG or gifts. So it's not looking
at the contents of the box. It's looking at
some kind of character. This it's making some kind
of fingers. Here's my code that I used to
hide to extract the hidden people. Me. It's
not a lot of hope in Python. It turns
out that because images are built in to the language
and choosing library, it's very easy to address all
the RGB values. And then to modify. This
is, you know, I need to understand how
the mod operator this is very early on in court
. You can explain it. But instead of just
modifying the image for a student to understand that I
can remove red eye, what I'd like to do
is take this and say, Why would I try
to hide information? Where's steganography used today. It
turns out that there are countries in which access to
the Internet is restricted, and transmitting information back and
forth is something that the government W he has something
everyone should do. In that case, hiding information
is something you might want. So hiding information.
And then it turns out something apparently actually is done
, especially hiding text in an image and transmitting the
image. You can only take out the text of
the other end. That's that's an interesting story,
And scaling it up to the level of cannot is
one of the things that computer science can control.
Which is that scale? Computational techniques confused and scared
for those of you that understands what's in common these
things, all of these involved finger a fingerprint of
the audio fingerprint of my U. R L,
which I think the U. R L shortening service
to a fingerprint of the image and all those techniques
. Why isn't this graphic I'm going to show you
? What's wrong with this from a computer science?
Here's I copied something from the show. Here's what
happens when they needed to look up things using computational
. Take hope. Yeah, flat. Yeah,
right. So obviously that here's what you see.
I'll explain it to you, which is way better
than your fingerprint comes up. And then other people
come up next and little minds get talked about.
And as the match gets closer, images slogan until
finally, the perfect condition. That's the one,
in fact. So when you're extracting information from the
two billion, does it actually pop them up one
at a time and then match them? Or does
it do something else? I hope that, you
know. Okay, So what I told you so
far is about content. I've tried to make the
case. That code is a good idea. But
it turns out that if all you do is change
your problems, that might help you change the audience
that you're dressing but things that I'm working on,
You also have to change your Pentagon. You have
to change not just what you are talking about.
How you talk about. Yeah, the problem is
one okay is not something that I do technically.
But I like to think of what I do is
probably one of the questions that I want. You
asked me when you see the message. Hey,
you have a problem. One of the problems that
I can take incorporating my class so I can get
across an idea in my feet. Because one of
the advantages of this approach is understand. Students will
understand better instead of having to recall isolated facts.
They have a story or problems they can eat and
playing their knowledge off. And those stories for somebody
that, according to the during those years, makes
it easier to just remember to bring that Colin comes
from the tight on you. No one seems to
have anything with that. What's important, even though
they have to understand that you like. So here's
the courses that I'm getting. This is all about
code. Where we go, there are two courses
that are underway. One of them, Google's network
. Google could have been at war for everything.
And this is the original Google under Sergio's office,
and this is the new group. What's the difference
? Escape. So what's happening here is what computer
science has to offer escape and the stories about what
we're going to do. Our this is one course
I'm going to tell you about real briefly before I
get to see a principle. This is of course
, I teach which covers copy left the DF bit
corn and traffic. Little apple, Skype, uh
, windows. All those things should come into play
. Maybe with code. I'll tell you about why
that coach, you have to find out where you
when you go on their ideas from giving quotes,
one of one of the government decides Mhm. So
if you can figure out which one Mm. Uh
, Newton has a famous quote I've seen larger than
others because I've stood over the Giants. We already
saw Candy in this quote about those features African and
David partners with computer scientists talk about the real and
why reinventing it is actually a good idea because you
know what? It's such a good idea that does
get reinvented off, he says. He worries about
ideas that only invented more. What kind of good
ideas only men want? A reinvention may be a
good idea. Now we re intention people for ideas
. And here's another quote about standard for computational thinking
. Outside the school, the computational literally allow civilizations
can do things that would be new to us in
the same way that the modern littoral society would be
almost incomprehensible. Pre literate culture by computational literacy.
I do not mean casual familiarity machine. So we
need to teach everybody something about writing code, something
about writing code. So I'm gonna skip this and
get Here's where we'll go. Why do you need
to teach people about writing code and, like coding
and airports competition thinking Because we don't want this book
to be the famous one. Physics for future presidents
. Why don't we have computer science? People aren't
working in our field. It's still so young.
Maybe that the people that are good at it are
still good at it. Instead of writing about being
good for the course that I alluded to this icy
square court, I want to tell you a little
bit about it and why? Why? It's working
into the principal portion with that, Okay, but
how many of you don't understand this together? They're
going to go on record. I don't right.
Really? How many people understand that there's an hour
that looks like this? Oh, really? Yeah
. Okay. Have you our understanding people, I
believe that you understand because you're spending all your time
away. Well, I don't believe everybody else in
the basic, but he's gonna raise your hand in
hand. It turns out that I have 240 people
have used to measure that. Don't understand this joke
and that's why they take. Of course, I
piece, which is supposed to teach them something about
between the protocol, the square, this intellectual property
and Internet Protocol. Understanding how they work together is
important for this Cyber literate citizens believe that I would
like to educate where they're not gonna want to write
code. But they do want to learn about how
things work and you can play those things together.
Here the topics of the course that you can kind
of read these are in the news. Every day
you can find something, no matter what paper you
read. Whatever online source of music, music,
not the New York Times. You're only reading Reddit
. It works because all this stuff is data.
What's going on with cybercrime? What's going on inside
the war? What's going on with the censorship?
All these things go into that sport. Unfortunately for
me, that course is dying. Mhm. I'm
going to show you why. Don, It is
free, but and tell you an interesting story that
gets me to my mother. So hopefully if this
doesn't fight, which doesn't. And right, it
turns out I have the Web. Make it.
If I have the left, I will show you
this video. You're quick. The former 82.
It's that might be able to get it. Oh
, yeah? How many of you don't know what
I mean is really or really mhm? Okay,
I'm sitting across from dinner last week with a couple
, both of whom are positions. My wife is
a position, and they asked, Oh, did
you explain to me what you need? I don't
get. And it turned out I couldn't. I
had a very hard time explaining what it means was
You hear me? I can't make it fine.
Yeah, Yeah. It turns out that I don't
have any divine though it's not. It's not funny
. Interesting. Unless you have a bond because you
need to hear the German in the back while you
see the words going. So let me tell you
what this video is about and what happened when I
made I made this two years ago when this was
a me. It's not so much a big meat
anymore. And it was about this course I teach
. I can swear I posted it to you too
. An hour later, it had been taken back
. Probably that happened. How would it get me
down? Yeah, that fact that would I'm out
. Good. Mhm. Mhm. It's a common
video. Holidays recognized the video. Use it.
Uh, they have one of those fingerprints. System
. It turns out that they can take a video
and they can make a fingerprint of it using audible
video magic, which is, uh, service they
subscribe to, and they take it down automatically.
Now, why do they take Why does YouTube take
down these things on That tells you probably you know
that. Yeah. Anybody else? Copyright. What
about copyright nations? Take it back. If they
take it down automatically, then according to the d
. M. C. A individual loan copyright act
, they are not liable for the fact that they
host untold numbers of copyright inclusion on YouTube. Today
. There are thousands of billions of copyright infringement.
You find them. Many of you look every day
. If you could have a mechanism by which they're
taken down at the request of the copyright holder,
especially automatically, they are protected their indemnified by the
U. S. Law from being prosecuted for assisting
indirectly copper 14 to the best interest to do that
mega upwards. Some of you know about mega upload
. It was Just wake up Rose to speak.
That's about code. Remember part of Mexico? A
group of people in New Zealand are basically ransacked by
police. US government that would they run in and
arrest some guy who has an interesting names driving the
car? Made millions of dollars are hosting illegal kind
. Why mega upload gets taken down and you keep
you can have a good discussion about that. I
think you could in your class. What's the difference
from the code of law versus the code of being
in New Zealand and flaunting your wealth? I'm not
sure lasted. See if this is, of course
, yeah, being done now. And it's being
done here at Virginia Tech as part of a national
initiative. So I want you to understand how that
works. We can understand where code comes into play
and where all this stuff it's supposed to be.
A first course in computer science. If it's the
first course in computer science. What are its record
? Yes, exactly your argument. That's what a
first course means. It doesn't mean you have to
take another course to get ready to take this course
. You should be able to take it knowing No
, it's designed to be an advanced placement, for
it is not going to supplant the existing Advanced Placement
Computer Science course. It's in addition to that.
AP is a national model, and this course is
about trying to change things at a national scale.
It's very difficult to change things the education at a
national scale because the local governments, state governments,
their state educators and all those states systems are completely
80 is one national because that exam has national class
national preference. A problem of making a new court
is that it doesn't exist in AP. Has always
been putting into high school, of course, is
already existing. Copy AP Psychology reasonably used 80 environmental
signs miserable if the statistic simply new AP calculus.
Very old, but they all model and exist in
court. This court was supposed to be designed from
scratch. It doesn't exist anywhere. You guys are
piloting one here here are the people that are making
up. It's a big group. It's a national
group. Mhm. This guy is sitting. So
he was part of the advisory board. There's a
big advisory port. Why does this course exist?
These are the demographics, and I know you probably
can't read that, But the purple is AP exam
, and the white blues is enrollment. So here
white, look here. Hey here, email.
There's not very many females. There are a lot
of white males taking sports African Americans there. This
AP course is not. This is a traditional people
. It's not growing at all where every other 18
courses growing up crazy. The demographics of who takes
the courts have not changed. In order to do
that, we would make a report to make a
new course. It never really existed before. It
was a complicated process, and it went over a
year giving a timeline in two slots, and it
resulted in a specific evidence centered design approach that led
to these big ideas here. The seven big ideas
of computer science. They're supposed to inculpate and influence
the course of the office. Creative activities, abstraction
, data algorithms, programming, Internet programming is one
of seven big ideas. So as we're trying to
develop a national exam around US, programming is only
the only thing. Yeah, To understand what this
course is going in order to make it to the
next stage we should have made We have to get
80 colleges to attest that this course is good Virginia
Tech and being a good man, not only is
it good, but you might get credit for,
like, 80 or you might get places. Or
you might say we will teach the course And this
attestation process. We didn't know at the time that
no one had ever succeed. We were told by
the College Board In order to get the next step
, we have to get 80 schools and have to
be the right. Mm. It can't just be
a little schools have to be 80 important. And
some schools are more important than others. And the
right school have to do it. And then given
this task before two other time to start being issues
, it would never succeed. This is the first
time maybe the computer science back together as a community
and all said this is okay. because normally,
as a discipline, we like to shoot down each
other like 1000 cooperatives. This is a good time
. It turns out that there are many schools teaching
, Of course, like this is like to see
us. One for at Harvard is a CS one
programming. And then there's a sea of principles.
Life course. There are many schools that have a
one and A C s principles it or immediately knocks
you. Apparently, I got the number wrong.
Next, live with You guys have a new course
assistance, of course that there. But I'm going
to give you the timeline so you can see that
we've got the curriculum in 11,000. We piloted five
colleges in 2010. 2011. This year is being
tired in 10 college department with 10 titles. That's
what's happening here in Hollywood, partner with the high
school. The idea is that after this, the
next stage is we need to deliver a natural exchange
, deliver national exam. We have what's called a
high stakes exam that will determine whether you get credit
for this course. We're trying to do a portfolio
based exams instead of just sitting for three hours in
deciding what an impact. Of course, you submit
a moratorium of your work, and that's interesting.
Because how does scale? How do you ensure that
the students are actually doing your homework for the future
being folded? We have to assess the highly courses
. Do you see why they're doing this? Code
will work, and then our goal is to liberate
this national event. So back up. Uh,
it turns out that all these plans to fail a
lot. So you have to. So I'm very
optimistic, Chief. Yes. And it turns out
the best. My last slide. And George,
my powerful major. I talked to her power.
I wouldn't go. Yeah, but I'm happy to
answer questions. Mhm. Okay. And I'm also
hanging around later to meet with people. If you
feel like you need to be there Mhm. Yeah
, I can tell you. Yeah, Yeah.
Wait a minute. Okay. Mhm. Yeah,
it is. Yeah. The question was how we
address institutions, universities and what the literature shows.
And if you look to see how that turns out
to be more about how you teach anyone with you
and it's very hard to get people to change how
these people, how they keep meeting, uh,
collaborative teaching teaching so that students are competing against each
other teaching so that its inquiry, based on the
package will give people problems to solve and think about
. So we're trying to do that. It's harder
to get people to do that here. But approach
that's being used that were espousing is don't keep your
same old collection. For about that, teachers and
the students are using the obligation of with days you
can give up problems. The tape on you.
That's the idea. We'll see. What? Yeah
. What? What? What we have, Peter
. Okay, All right back. How does mhm
President? Yeah, he said you keep that.
Ones that are advanced. Kristen, I think the
question is, students come in with a variety of
experiences, ability, levels in this report, the
students already know are really good and getting really fast
. What? What? What are you? And
I think this applies to anything. What? But
in this particular case, at least for this course
, is not intended to be the first course of
produce Hundreds. It's intended to be a broad course
that everybody, including potentially my guess is that if
you come in already knowing how to program and you're
probably gonna get out, that's a good idea or
not. This course is designed to be a stand
alone. This could be the only part you ever
take become part of history. And if you really
kind of take off on the coding and programming side
, maybe one of the line. But so that's
one answer. The other answer is the same as
that reply anywhere. What do you do? You
have one course. Students already know what to do
, and that's kind of the state of, Well
, you give them challenge. Shut them off because
you've got to shut these people up because if they
start answering every question that gets asked, people don't
them get going so that that's my routing said I'm
not sure the demographics are medicals. That's cool.
First started there as cutthroat as anything, and it's
all the time. I don't need to stop almost
like he was about. It seems to be something
else. There's another component of this. What makes
these okay, Mhm ingredient is interesting, so I'm
not. I'm not sure there was a question,
but 11 of the observations made with medical school Cutthroat
. It's all packed. It turns out that problem
is, learning has a bigger foothold in medical school
. That's true than anywhere else. That's true.
But certainly Yeah, mhm, Yeah, I'm thinking
more like, say, 10 years ago, right
? Mhm. This footprint is just like all the
time is that women went into that. So I
think the question is, why do we make it
a question? Hey, 55% of the people who
are women and and they don't seem to mind the
fact they or the and they're willing to put up
with it because they all want to be doctors.
And the problem that we have in computer sciences no
one knows. If you want to be a software
engineer, that's fabulous. But if all we're gonna
do is educate software in years and we don't even
need to actually, But this is really for me
, I don't know. My personal work different happened
. You asked me about I don't care about that
. I'm interested in because I want to be an
educator and keep a wide group of everybody. How
beautiful is on it. So I want to get
all those things in here that are both in here
into the hands of the watch. And in order
to do that, we have to get problems that
are relevant to you. You won't know that.
You want to do this. You know, you
didn't grow up wanting to be a doctor. And
the word shows on TV about how you can combine
your interest in intellectual property. Internet protocol, where
you grew up, knowing that position was something respectable
. So I think there's kind of a whole set
of society have the threat that makes us different than
that. Maybe you should stop. So that uh
huh. To the book? Yeah. The only
thing he has said he standard. And that Excellent
question. Yeah. Was it fine? Okay,
that they work. So the question was, you
can accommodate and let me make clear I failed.
Probably I wanted to tolerate. Morning. It turns
out it's way too hard in the problem based on
a comic. So I changed my would be probably
spend because problem based learning here can read. The
literature is unbelievably kind of heavy duty on looking structure
does what you do, and I just I failed
, so I decided to change my terminology and all
problems center mean instead of teaching about groups. I
don't look at this problem, and we're going to
study the problem and to figure out what techniques you
need to use to solve the problem. So that
instead of thinking in this course, is about groups
and it states this course is about tag clouds is
stigma. And then we use the most problems to
get at the station you want. But I succeed
for me. But I haven't even succeeded for all
of that. My department, because many of them
are very comfortable with the textbook, has we're on
the move. They don't like to have to do
that. It's really interesting. Yeah, I fight
battles locally. Uh huh. Mm hmm. But
at least the conversation about the problems that you could
say versus steganography I would be way happier having that
conversation. And so we will have rashes up the
conversation, and you will succeed completely.