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690 lines
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690 lines
27 KiB
<?xml version="1.0" encoding="iso-8859-1"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN"
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"http://www.w3.org/Math/DTD/mathml2/xhtml-math11-f.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<title>Answers for young people - Tim Berners-Lee</title>
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<meta http-equiv="content-type"
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content="application/xhtml+xml; charset=iso-8859-1" />
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<link href="general.css" rel="stylesheet" type="text/css" />
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</head>
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<body xml:lang="en">
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<h3><a href="Overview.html"><img alt="Tim Berners-Lee"
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src="../../Press/Stock/Berners-Lee/2001-eur-head-quarter.jpg" /></a></h3>
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<p>Note: Some of these questions are now answered in much more depth in my
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book, <a href="Weaving/Overview.html"><em><strong>Weaving the Web.
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</strong></em></a>Adults, see also: <a href="FAQ">the main FAQ</a>.</p>
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<h1>Answers for Young People</h1>
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<p>Doing a report? Want to figure out how the web works?</p>
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<p>I have put here some answers to questions that children of various ages
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(6-96) have asked.</p>
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<p>If you need the answers for a school project or just because you're
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interested, then feel free to quote them from here. In your report, please
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say where you got them from.</p>
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<p>This is just one page for kids of all ages so some you might feel the
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answers are too simple and some too complicated. I hope you find it useful,
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anyway.</p>
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<ul>
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<li><a href="#Where">Where were you when you invented the WWW?</a></li>
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<li><a href="#What">What made you think of the WWW?</a></li>
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<li><a href="#What1">What happens when I click on a link?</a></li>
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<li><a href="#invent">Did you invent the Internet?</a></li>
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<li><a href="#Just">Just like that?</a></li>
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<li><a href="#keep">Why do you keep saying everything is so simple?</a></li>
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<li><a href="#tell">Can you tell me more about your personal life?</a></li>
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<li><a href="#doing">I need a primary source for a project on you</a></li>
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<li><a href="#L325">I'm interested in math more than what's at school -
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what is fun?</a></li>
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<li><a href="#think">Was the WWW a good thing or a bad thing?</a></li>
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</ul>
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<p></p>
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<p></p>
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<h2><a id="Where">Where were you when you invented the WWW?</a></h2>
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<p>I was working in a physics laboratory called <a
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href="http://www.cern.ch/">CERN</a>. (CERN is in Geneva, Switzerland.
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Switzerland is near the middle of Europe.)</p>
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<p>At CERN, people study <em>High Energy Physics</em>. That is the physics of
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really really small particles - particles much smaller than atoms. It turns
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out that if you want to investigate really really small things, you need huge
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machines called accelerators to smash particles together really hard. Then
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you have huge gadgets (about the size of a house) which detects what happens,
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and what bits fly off, so you can figure out whether you managed to make any
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new types of particle.</p>
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<p>CERN is a big place - a few thousand people work there. Many of them are
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scientists whose jobs are at universities in different places in the world,
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and they come to CERN because they need to use the huge accelerators at
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CERN.</p>
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<h2><a id="What">What made you think of the WWW?</a></h2>
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<p>Well, I found it frustrating that in those days, there was different
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information on different computers, but you had to log on to different
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computers to get at it. Also, sometimes you had to learn a different program
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on each computer. So finding out how things worked was really difficult.
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Often it was just easier to go and ask people when they were having
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coffee.</p>
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<p>Because people at CERN came from universities all over the world, they
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brought with them all types of computers. Not just Unix, Mac and PC: there
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were all kinds of big mainframe computer and medium sized computers running
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all sorts of software.</p>
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<p>I actually wrote some programs to take information from one system and
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convert it so it could be inserted into another system. More than once. And
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when you are a programmer, and you solve one problem and then you solve one
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that's very similar, you often think, "Isn't there a better way? Can't we
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just fix this problem for good?" That became "Can't we convert every
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information system so that it looks like part of some imaginary information
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system which everyone can read?" And that became the WWW.</p>
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<h2><a name="What1">What happens when I click on a link?</a></h2>
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<p>Actually, it was a grown up who asked this very reasonable question. When
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you understand this, then you will understand the difference between the
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Internet and the Web. And you will realize that it is all quite simple!
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:-)</p>
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<p><small>(You can skip the bits in small type)</small></p>
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<p>When you are reading a web page, the computer isn't showing you everything
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about the link. Behind the underlined or colored bit of text which you click
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on is an invisible thing like <em>http://www.w3.org/</em>. Its called a URL.
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This is the name of the web page to which the link goes. (The web page you
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are reading has this one:
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<em>http://www.w3.org/People/Berners-Lee/kids</em>). Behind each link, hidden
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from you, is the URL of the other web page, the one you'd get to if you
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followed the link.</p>
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<p>When you click on a link, your computer takes this URL. It wants to get a
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copy of the web page. There are a few different ways of doing this. The one
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I'm going to tell you about is just used for URLs which start<em>http:
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.</em></p>
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<p><small>(This whole recipe I'm going to tell you, which your computer uses
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for getting web pages, is called the </small><em><small>HyperText Transfer
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Protocol</small></em><small>. That's what HTTP stands for. There are other
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protocols. But this is the most common one. )</small></p>
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<p>If the URL starts with <em>http:</em>, then the computer takes the next
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bit of the URL, between the // and the /. It might be <em>www.w3.org</em> for
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example. This is the name of the web server. However, It can't communicate
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with the web server until it knows its computer number, because the Internet
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actually works with numbers.</p>
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<p><small>(A computer number is actually called its Internet Protocol
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Address, or IP Address. It is normally written as four numbers with dots,
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like </small><em><small>192.168.0.1</small></em><small>)</small></p>
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<p>So there will two stages to this - first, finding out the number of the
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web server, and then asking the web for a copy of the web page.</p>
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<p>Your computer makes up a <dfn>packet</dfn> of information. An Internet
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packet is a message, a bit like a short email or a long text message. The
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packet starts off with the number of the computer the packet is going to, and
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then the number of the the computer which sent it, and then it has what the
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packet is about, and then whatever it is one computer is sending to the
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other.</p>
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<p>Now all over the Internet there are special computers whose job is to keep
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a list of computer names and numbers. When your computer is set up, it is set
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up to know the internet number of one of these. Your computer sends off the
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packet to it, saying it wants to know the number of <em>www.w3.org</em>.</p>
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<p><small>(A computer which can look up computer names -- <dfn>domain
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names</dfn> as they are called -- is called the <dfn>Domain Name
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Service</dfn> (DNS) server in the network preferences if you really want to
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know. When a DNS server looks up a computer name, it either knows it because
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it has it in a list, or it just asks another DNS server which knows more
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names.)</small></p>
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<p>How does the packet get there? Simple. Your computer sends it down the
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ethernet connection or phone line from your computer, or it transmits it by
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radio to a base station which sends it down some wire. Whatever that wire
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goes through, eventually it connects to some other computer (maybe one in the
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cable company, or phone company).</p>
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<p>The Internet is a net -- really shaped like real net like a fishing net --
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of computers all connected together by various cables. Each computer, when it
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gets a packet, looks at it and sees what computer number it is being sent to.
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It then just passes it on to the next computer in the net, in the general
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direction toward its destination. Pretty simple? yes, well, it is simple. The
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packet gets passed on until it gets to its destination. Typically, a packet
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might be passed on by more than 10 computers before it arrives.</p>
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<p><small>(This way of getting a packet to its destination is called the
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</small><dfn><small>Internet Protocol</small></dfn><small>(IP))</small></p>
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<p>In this case, the destination was the name server. The name server looks
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up the number of the computer www.w3.org from its name.</p>
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<p>Of course the name server knows the number of your computer, because that
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was in the packet too. So it sends a reply packet to tell you computer the
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number it needed.</p>
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<p>Ok. Your computer now knows the number of the web server,
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<em>www.w3.org</em>. So it goes back to the URL -- remember the thing which
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started with <em>http:</em>? Lets say the URL behind the link was
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<em>http://www.w3.org/People/Berners-Lee/FAQ</em> . It has used the
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www.w3.org bit to find the number of the web server which has a copy of the
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page. Now it send off a request to that server asking it for the web page. It
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sends the whole URL, and the server sends back a copy.</p>
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<p>The only problem is that the web page won't fit in a packet. Packets can
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only be around 512 bytes - about long enough for a text message of 500
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characters. Even the request that your computer sends off can be longer than
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will fit in a packet. So what happens is the computer just breaks the message
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into parts, and sends each part in a packet. I told you this isn't rocket
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science. It just like a television series coming in installments. It also
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puts in each packet a packet number so that the other computer can make sure
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its got all the parts and got them in right order.</p>
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<p><small>(This method of splitting message sup into packets and putting them
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back together again has a name, which you don't have to remember. It is
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<dfn>Transmission Control Protocol</dfn>, or TCP. So that's what people mean
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when they talk about TCP/IP.)</small></p>
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<p>So your computer gets back a bunch of packets with bits of the web page in
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them. It puts them in order and displays them on your screen. There are
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special codes (called HTML tags) which tell it when to do things like
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headings and bold and italics and ... oh, of course... links. Yes, every time
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it finds the HTML tag for a link, it displays the text specially (like blue
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and underlined) and makes a note of the URL of the linked page. Because at
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any time, you could click on the link, and it'll be doing this stuff all over
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again.</p>
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<p>@@@ This really needs lots of nice diagrams @@@</p>
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<h2><a>Did you invent the Internet?</a></h2>
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<p>No, no, no!</p>
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<p>When I was doing the WWW, most of the bits I needed were already done.</p>
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<p>Vint Cerf and people he worked with had figured out the Internet Protocol,
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and also the Transmission Control Protocol.</p>
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<p>Paul Mockapetris and friends had figured out the Domain Name System.</p>
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<p>People had already used TCP/IP and DNS to make email, and other cool
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things. So I could email other people who maybe would like to help work on
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making the WWW.</p>
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<p>I didn't invent the hypertext link either. The idea of jumping from one
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document to another had been thought about lots of people, including Vanevar
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Bush in 1945, and by Ted Nelson (who actually invented the word hypertext).
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Bush did it before computers really existed. Ted thought of a system but
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didn't use the internet. Doug Engelbart in the 1960's made a great system
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just like WWW except that it just ran on one [big] computer, as the internet
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hadn't been invented yet. Lots of hypertext systems had been made which just
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worked on one computer, and didn't link all the way across the world.</p>
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<p>I just had to take the hypertext idea and connect it to the TCP and DNS
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ideas and -- ta-da! -- the World Wide Web.</p>
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<h2><a>Just like that?</a></h2>
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<p>No, actually the inventing it was easy. The amazing thing which makes it
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work is that so many people actually have made web servers, and that they all
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work the same way, on the Internet. They all use HTTP.</p>
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<p>So the difficult bit was persuading people to join in. And getting them to
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agree to all use the same sort of HTTP, and URLs, and HTML. I'm still doing
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that sort of thing. The World Wide Web Consortium (W3C) is like a club of
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people and companies who feel the Web is important, and keeping it working is
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important, and making it even better and even more powerful is important. I
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am the director of W3C (I started it) but thousands of people are now working
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on all kinds of wonderful things.</p>
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<h2><a>Why do you keep saying everything is so simple?</a></h2>
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<p>Well, because it is basically.</p>
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<p>No, honestly...</p>
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<p>I want you to know that you too can make new programs which create new fun
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ways of using computers and using the Internet.</p>
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<p>I want you to realize that, if you can imagine a computer doing something,
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you can program a computer to do that.</p>
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<p>Unbounded opportunity... limited only by your imagination.</p>
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<p>And a couple of laws of physics.</p>
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<p>Of course, what happens with computers is that you have a basic simple
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idea and then you have to add things on to it for practical reasons. So
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real-world computer programs can end up with a lot of stuff in them. If they
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are good, they are still simple inside.</p>
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<p></p>
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<h2 id="What2">What did you do when you were a child?</h2>
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<p>I grew up in south-west London. I wasn't very good at sports. When I was
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11 I went to a school which was between two railway tracks, so I saw lots of
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trains and started train-spotting. I also had a model railway in my bedroom.
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It was a long thin layout with a 4-track station in the middle, and on each
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side pairs of tracks going off into tunnels to actually loop back to each
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other.</p>
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<p>I made some electronic gadgets to control the trains. The I ended up
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getting more interested in electronics than trains. Later on, when I was in
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college I made computer out of an old television set. I bought the television
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from a repair shop down the road for £5 (about $7).</p>
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<p>My mother and father were both working with the very early computers when
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they met. Later on, my mother taught maths in school. They taught me that
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maths is a lot of fun. (In England, mathematics is "maths", in the USA,
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"math").</p>
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<p>When I went to Oxford University, I studied physics. I thought that
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science might be more practical than maths, halfway between math and
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electronics. In fact it turned out to be very special subject all of itself,
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and fascinating for all that.</p>
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<h2><a>Can you tell me more about your personal life?</a></h2>
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<p>No, I don't want to - sorry. I like to keep work and personal life
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separate. What is on the web on this page and my home page is all there is.
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Please do not email me asking for more information for school projects, etc.
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Look -- if you had written a program like WorldWideWeb -- which you well
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might --- would you want everyone to know what you had for breakfast? No, you
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see? Ok. Thank you for your understanding.</p>
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<p></p>
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<h2 id="doing">But I am doing a project where we have to get "primary"
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sources, which means I have to interview the subject. And I'm doing it on
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you. So I have to interview you.</h2>
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<p>I'm sorry, I don't have time to talk to everyone individually. Please use
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these web pages.</p>
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<p></p>
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<p></p>
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<h2 id="L325">I'm interested in Math -- what exciting stuff is there we don't
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do at school?</h2>
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<p>Some kids find solving math problems is fun, and like the power of having
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new techniques, and imaging new math concepts. If you are one of those, and
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you are wondering what bits of math might be fun to follow up on your own or
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with friends or friendly adults, here is an attempt to explain some paths
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which connect together. Some of it is easy, some hard, but honestly which is
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which for you depends on what your mind happens to grasp, and how well it is
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explained! These are some of the bits I found interesting. This is NOT an
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explanation - you will need books and people for that . It is just a sort of
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list of places you might want to go.</p>
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<p><strong>Vectors</strong> are fun. Vectors are quantities with direction,
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like not just how fast something goes but which direction it is going in.
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They can be written as three numbers instead of one. <em>(The examples in
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this FAQ will only work is your browser supports MathML, which is rare. If
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your browser supports MathML, the following will be vertical, not
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horizonal.)</em></p>
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<p><math xmlns="http://www.w3.org/1998/Math/MathML">
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<mrow>
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<mo>(</mo>
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<mtable>
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<mtr>
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<mtd>
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<mn>10</mn>
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</mtd>
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</mtr>
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<mtr>
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<mtd>
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<mn>2</mn>
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</mtd>
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</mtr>
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<mtr>
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<mtd>
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<mn>4</mn>
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</mtd>
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</mtr>
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</mtable>
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<mo>)</mo>
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</mrow>
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</math></p>
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<p>Vectors are fun partly because they are very visual. When you write
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equations using vectors, you define shapes in 3D, and how things move, and so
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on.</p>
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<p>When you've done a bit of <strong>algebra</strong>, then simultaneous
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equations are good thing to play with. You don't have to do complicated ones,
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just look at "linear" equations where you have say 3 equations and 3
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variables, say x, y and z.</p>
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<p><math xmlns="http://www.w3.org/1998/Math/MathML">
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<mtable>
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<mtr>
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<mtd>
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<mi>x</mi>
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<mo>+</mo>
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<mi>y</mi>
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<mo>=</mo>
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<mn>3</mn>
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</mtd>
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</mtr>
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<mtr>
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<mtd>
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<mi>x</mi>
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<mo>-</mo>
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<mi>y</mi>
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<mo>=</mo>
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<mn>1</mn>
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</mtd>
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</mtr>
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<mtr>
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<mtd>
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<mn>3</mn>
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<mi>y</mi>
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<mo>-</mo>
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<mi>z</mi>
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<mo>=</mo>
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<mn>0</mn>
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</mtd>
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</mtr>
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</mtable>
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</math><br />
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</p>
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<p>Because you've done vectors, you can visualize each equation as a plane in
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3d, and the equations together define a point with a given x, y and z.</p>
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<p>Once you've got the hang of that, look at
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<strong>transformations</strong> where a set of linear equations define a new
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(x', y', z') in terms of any original point (x, y, z).</p>
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<p><math xmlns="http://www.w3.org/1998/Math/MathML">
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<mtable>
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<mtr>
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<mtd>
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<mi>x</mi>
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<mo>+</mo>
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<mi>y</mi>
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<mo>=</mo>
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<mi>x</mi>
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<mo>'</mo>
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</mtd>
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</mtr>
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<mtr>
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<mtd>
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<mi>x</mi>
|
|
<mo>-</mo>
|
|
<mi>y</mi>
|
|
<mo>=</mo>
|
|
<mi>y</mi>
|
|
<mo>'</mo>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mn>3</mn>
|
|
<mi>y</mi>
|
|
<mo>-</mo>
|
|
<mi>z</mi>
|
|
<mo>=</mo>
|
|
<mi>z</mi>
|
|
<mo>'</mo>
|
|
</mtd>
|
|
</mtr>
|
|
</mtable>
|
|
</math></p>
|
|
|
|
<p>Two neat things. One is these transformations actually correspond to 3-d
|
|
transformations such as squashing space or rotating it, or squishing it
|
|
sideways. This is quite visual, and thinking of the 3-d transformation is
|
|
sometimes a quick way of doing things with the equations.</p>
|
|
|
|
<p>Second neat thing: because you've used stacks of 3 numbers as vectors to
|
|
represent points, you'll be happy representing the numbers in the equations
|
|
in a 3x3 block called a <strong>matrix</strong>. This way you can write the
|
|
transformation as a thing called matrix multiplication. You learn how to
|
|
multiply matrices.</p>
|
|
|
|
<p><math xmlns="http://www.w3.org/1998/Math/MathML">
|
|
<mrow>
|
|
<mo>(</mo>
|
|
<mtable>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>x</mi>
|
|
<mo>'</mo>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>y</mi>
|
|
<mo>'</mo>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>z</mi>
|
|
<mo>'</mo>
|
|
</mtd>
|
|
</mtr>
|
|
</mtable>
|
|
<mo>)</mo>
|
|
</mrow>
|
|
<mo>=</mo>
|
|
<mrow>
|
|
<mo>(</mo>
|
|
<mtable>
|
|
<mtr>
|
|
<mtd>
|
|
<mn>1</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>1</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>0</mn>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mn>1</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>-1</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>0</mn>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mn>0</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>3</mn>
|
|
</mtd>
|
|
<mtd>
|
|
<mn>-1</mn>
|
|
</mtd>
|
|
</mtr>
|
|
</mtable>
|
|
<mo>)</mo>
|
|
</mrow>
|
|
<mrow>
|
|
<mo>(</mo>
|
|
<mtable>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>x</mi>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>y</mi>
|
|
</mtd>
|
|
</mtr>
|
|
<mtr>
|
|
<mtd>
|
|
<mi>z</mi>
|
|
</mtd>
|
|
</mtr>
|
|
</mtable>
|
|
<mo>)</mo>
|
|
</mrow>
|
|
</math></p>
|
|
|
|
<p>or just</p>
|
|
|
|
<p><strong>x</strong>' = <strong>M</strong> <strong>x</strong></p>
|
|
|
|
<p>where the bold letters stand for vectors and matrices. Suddenly all kinds
|
|
of things fall into place. To make a combined transformation, you just
|
|
multiply two matrices together. You naturally start wondering about how to
|
|
<em>undo</em> a transformation, which is finding the <em>inverse</em>
|
|
transformation, which is finding the inverse of a matrix. And then you
|
|
realize that this is just the same problem as solving the linear equations
|
|
you had earlier. So any time you can see how to solve the equations, you can
|
|
find the inverse matrix. Also, there is a way of working out the inverse of a
|
|
3x3 matrix, so you can always solve 3x3 equations (when a solution exists).
|
|
It is this way everything fits together which makes math fun and powerful.</p>
|
|
|
|
<p>Another branch you might be interested in is <strong>calculus</strong>.
|
|
This is about things changing and moving, to its very connected to physics,
|
|
skiing, driving cars, flying planes, and so on. So it can also be fun to
|
|
visualize. When you study calculus, you start off by thinking about how (say)
|
|
the speed of a ball changes in a particular millisecond, and how its position
|
|
changes. There is a lot of calculus where you know, say, how something's
|
|
speed changes with time, and you want to figure out where it gets to. How
|
|
fast a function changes is another function. Finding it is called
|
|
<em>differentiating</em> the first function. The inverse is called
|
|
<em>integrating</em>. Some people find learning and puzzling out how to
|
|
differentiate and integrate all kinds of functions interesting.</p>
|
|
|
|
<p>But if you have done vectors and matrices then you can connect that to the
|
|
ideas of calculus, and you have new powerful mental tools. You can now write
|
|
equations about the force on something and its acceleration as vectors.</p>
|
|
|
|
<p><strong>f</strong> = m <strong>a</strong></p>
|
|
|
|
<p>says the force (a vector) on something is equal to the acceleration (how
|
|
much its velocity is changing, another vector) times the mass of the thing.
|
|
You can figure out how things like spaceships move in 3d space with time.</p>
|
|
|
|
<p>From there, you can think about values (like density, or pressure, or
|
|
temperature) which have a single (non vector) value, but a different value in
|
|
each place. You can think about how those values change with place. How does
|
|
the pressure in a swimming pool change with depth? Why? Things which have
|
|
values all over the place are called <strong></strong><em>fields</em>. Think
|
|
of the pool being filled with little numbers showing the pressure at that
|
|
place.</p>
|
|
|
|
<p>Then you can just put what you know about vectors together with what you
|
|
know about fields, and think of values which are different in different
|
|
places and times, and also have direction. They are vectors. Imagine a
|
|
swimming pool full of little arrows, each arrow showing (by size and
|
|
direction) how fast and which way the water is moving there. Imagine what
|
|
happens when someone dives in. These are called <strong>vector
|
|
fields</strong>. It turns out that when you do calculus with vector fields,
|
|
you have really neat little results about how stuff swirls around, about how
|
|
it squashes (or doesn't), and so on. When you connect how things change with
|
|
position with how they change with time, then you can show waves happen. And
|
|
just as it seems that the equations are getting complicated again, then
|
|
suddenly get simple. It turns out that the differentiation in space can be
|
|
written as a single "vector operator", called <em>dell</em> and written<math
|
|
xmlns="http://www.w3.org/1998/Math/MathML">
|
|
<mo>∇</mo>
|
|
</math></p>
|
|
|
|
<p>This makes all the equations writable in much less space (without even any
|
|
x's and y's and z's).</p>
|
|
|
|
<p>One of the significant equations which you get from look the physics of
|
|
all this is the wave equation, which tell you about sound waves in a swimming
|
|
pool and even <a
|
|
href="http://scienceworld.wolfram.com/physics/MaxwellEquations.html">Maxwell's
|
|
Equation</a>s which show that light waves follow from the properties of
|
|
electricity and magnetism.</p>
|
|
|
|
<p>Another branch of this which connects to matrices is the eigenvector
|
|
concept. For any transformation, it turns out there are some vectors which
|
|
end up being stretched or shrunk but not changed in direction. These are
|
|
called <strong>eigenvectors</strong>. It turns out that for lots of
|
|
interesting problems, the eigenvectors are at right angles to each other,
|
|
just like the x y and z axes. In fact, if you turn the problem around in your
|
|
mind, and use the eigenvectors as the axes, then suddenly the problem becomes
|
|
really simple. The complicated equations untangle and turn into a set of
|
|
unconnected simple equations. Eigenvectors are finding out how complicated
|
|
things (like a car suspension) behave. It also turns out that quantum
|
|
mechanics says that the same equations are used to find out how atoms behave.
|
|
Also, it turns out that when search engines like Google look at a mass of web
|
|
links around a topic, the eigenvectors of the link matrix correspond to
|
|
things the web pages are about, and finding them allows one to find the most
|
|
relevant page for that topic. So eigenvectors are a really useful concept.</p>
|
|
|
|
<p>I guess I've used physics as the hook for most of this math, and that is
|
|
one reason why it is interesting personally for me. If that doesn't interest
|
|
you so much, then maybe the math of prime numbers will. Check out modulo
|
|
arithmentic, Euler's theorem, and work your way to the RSA algorithm for
|
|
public key cryptography. There are lots of other areas of math of course. And
|
|
lots of books on each. And web sites, I'm sure. But there are some of my
|
|
suggestions if you are looking for a map of things to look for. The main
|
|
thing is, to have fun.</p>
|
|
|
|
<h2><a>So do you think the Web is basically been a good idea or a bad
|
|
one?</a></h2>
|
|
|
|
<p>Some people point out that the Web can be used for all the wrong things.
|
|
For downloading pictures of horrible, gruesome, violent or obscene things, or
|
|
ways of making bombs which terrorists could use.</p>
|
|
|
|
<p>Other people say how their lives have been saved because they found out
|
|
about the disease they had on the Web, and figured out how to cure it.</p>
|
|
|
|
<p>I think the main thing to remember is that any really powerful thing can
|
|
be used for good or evil. Dynamite can be used to build tunnels or to make
|
|
missiles. Engines can be put in ambulances or tanks. Nuclear power can be
|
|
used for bombs or for electrical power.</p>
|
|
|
|
<p>So what is made of the Web is up to us. You, me, and everyone else.</p>
|
|
|
|
<p>Here is my hope.</p>
|
|
|
|
<p>The Web is a tool for communicating.</p>
|
|
|
|
<p>With the Web, you can find out what other people mean. You can find out
|
|
where they are coming from.</p>
|
|
|
|
<p>The Web can help people understand each other.</p>
|
|
|
|
<p>Think about most of the bad things that have happened between people in
|
|
your life. Maybe most of them come down to one person not understanding
|
|
another. Even wars.</p>
|
|
|
|
<p>Let's use the web to create neat new exciting things.</p>
|
|
|
|
<p>Let's use the Web to help people understand each other.</p>
|
|
|
|
<p></p>
|
|
|
|
<p></p>
|
|
|
|
<p></p>
|
|
<hr />
|
|
<address>
|
|
<a href="/People/Berners-Lee/">TimBL</a>
|
|
</address>
|
|
</body>
|
|
</html>
|