`
`.
`<html>
`Page Title
`{head}
`<title>l~low TEE'l'ntemet Horks<ft§ . >
`(meta http—equiv=“Content-Tgpe“ conten
`<Xheaa>
`
`Background Color
`<bodggeg'aat-qget4tFFFFFF“ l inkw‘aeaaam"
`(div id="uag§hl" stgle="position:abeoiu
`(div id="ta er " stgle=”position:absot
`(div id=" EiSF - stgle="position:abeoi‘
`(div id=“Lager4" stgle=”position:absol.
`(div id="Lager5" stgle="position:absolu
`(div id="Lagerfi" stgle="position:absott
`<p>(font size="3" face=”Vendana,
`flnia
`what’s happening behind the screens
`(p>(font size=“3“ faoe="¥endana,
`firi
`about creating your own Heb site, at
`(p}<font size="3" face="Vendana, flri
`all magic and madness to gou?<f
`finit
`(p><font size=”3“ face="Verdana,
`have come to the right place! Thie
`out of the Internet and explaining
`<p>anbsp; (/p>
`(p><font face=“Vendana, finial, Helve
`about:(.r’b}</font>(.r‘p>
`<p>(b}(font face="Vewduna, finiat, Mei
`Hnatomg of a Heb Site<fa§<£font§€
`<pb<b¥<font face-"Vendana, finial, Hal
`Hrchitecture of the Neb<,-"'t’ont}{.ft
`<p>(b>(font faoe="VePdana, finial, Hel
`Technologies on the Neb4ffomt}t
`(p> (fp}
`<p><font face="Verdana, Hhial, Hale
`<p><font faoe="Vendana, finial, Hela
`site uou will also find lots of k
`Hide Neb.(/font>(/Fv>
`dam
`(div id="Lager?" stgle="position:absol
`<p><font color="*999999"}<b><fon
`5i
`<p><font color="“9999CC"}<a href=“L.l
`<p><font color=““999999”>(b>{font 5i
`l<br>
`(a href="fiiflistawt.html">Hhat
`<p><font color=“*999999”}<b>{fen
`ll<br> Hyperlink
`(a href='part822tart.html“>The lr,a
`<p><font color="*999999">(b>{fon a.
`lll<br>
`(a href=”part835tart.html“>Connecti
`<p><font color=“*999999”><b>€fot
`a:
`lV<br>
`(a href=“part24start.html">Commani
`<p>(font color="“999999"><b>{fu
`at
`V(br>
`(font color="*5655CC">(a href=”pah
`<p><font oolor=”#999999"><b><fofi
`sf
`Vl<br>
`(font colon="#565600“>(a hraf=“Lr ts
`<p><font color="“999999"><b><€on
`5i
`Hll<br)
`(font color="“fififificc"><a href:”par
`Sp)(font color="*999999">(b>{fon sl
`Vlll<br5
`(font colori“*fififi5t0"><a hnaf=”pmh
`
`the internettfaxflant><,r'f.:m;v
`2: i
`
`<p>(font color=”*999999“><b}(fofi
`lX<bn>
`(font color="*fifififiCC"><a hnef‘"pn
`<p)€font
`color="*999999"><b>€frp
`_i
`to (hr)
`_
`Table of Pontents(flnut><fa>€
`<p>&nhsp;({p>
`<p> <£n>
`(fem
`(div id=”Lager8“ stgle=“po5ition:absoh
`(lmg arc="bfi!fifi$fi" width="151" height="7
`(div id="Lager9" stgle=”position:abso
`(div id="Lagerla" stgle="position:absa
`(div idr-"LageMl" stg1e="position:abso
`(food?
`<1html>
`
`e g
`
`fi
`:1L-
`
`is
`
`as
`
`a The coding in the HTML files tells your browser how to dis—
`play the text, graphics, links, and multimedia files on the
`home page. The HTML file your browser loads to display the
`home page doesn’t actually have the graphics, sound, multi-
`media files, and other resources on it. Instead, it contains
`HTML references to those graphics and files. Your browser
`uses those references to find the files on the server and then
`
`display them on the home page.
`
`[I The Web browser also interprets HTML tags as links to other
`Web sites, or lu ulher Web resources, such 05 graphics, mul-
`timedia files, newsgroups, or files to download. Depending
`on the link, it performs different actions. For example, if the
`HTML code specifies the link as another home page, the
`browser retrieves the URL specified in the HTML file when
`the user clicks the underlined link on the page. If the HTML
`code specifies a file to be downloaded, the browser down—
`loads the file to your computer.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Many types of files exist on the Internet that Web browsers can't display.
`In particular, this pertains to many kinds of multimedia files, such as
`sound, video, and animation files. Still, there are often references to
`these types of files on Web pages. To View or play these files, you need
`what are called helper applications and plug-ins. You must configure
`your Web browser or operating system to launch these helper applica-
`tions and plug-ins whenever you click an object that needs them in order
`
`
`
`
`to be viewed. Helper applications and plug-ins also can be used for dis-
`
`playing virtual reality pages, for-chatting on the lntemet, ahdeorReerIwu
`
`
` name... .. 4 .
`ling oth'erlnterrjet-tasks.
`‘
`—-I U 1
`.- ->-—r T 4-
`_..._
`'
`- _ —-—-—--I.-
`
`
`.
`
`
`
`The meanings of tags are easily decipherable. Every HTML tag, or
`
`instruction, is surrounded by a less-than and a greater-than sign—<P>.
`
`Often tags appear in pairs, the beginning tag and the ending tag. They
`
`
`are identical except for a simple slash in the end tag. So, a paragraph of
`
`
`text frequently is surrounded by tags such as this: <P> Paragraph of
`"“ —_J
`text.</P>. Also, tags artinpt case sensitive. s_P> equals <p>.
`
`
`
`151
`
`151
`
`
`
`
`
`
`
`What Common Browser
`
`Error Messages Mean
`
` DNS Server
`
`Server Does Not Have a DNS Entry When
`you type a URL in your browser to visit a
`site, your computer contacts a server called
`a Domain Name System (DNS) server. The
`DNS server translates the URL into the iP
`
`number that computers can understand-
`and after it does that, your browser can go
`to the site. (For more information about
`DNS servers, see Chapter 5, "How internet
`Addresses and Domains Work”) if you get
`an error message telling you the server
`doesn't have a DNS entry, it means that the
`server doesn't have a listing for the URL you
`typed. This usually means either you typed
`the URL incorrectly or something is wrong
`with the DNS server. Check the URL and
`retype it.
`
`503 Service Unavailable This is a catch-all error
`
`message for a variety of problems, but all of them
`mean that the Web site has been incapable of being
`contacted by your browser. The problem might be
`that the site’s server has crashed because of too
`
`much traffic or that there’s network congestion.
`
`‘1
`0'.
`
`Iit.“
`‘
`2 rr‘
` "»\do
`‘ SWEb Sé‘héeri
`
`I 403.9 Access Forbidden. Too Many Users Are
`Connected. Some Web sites recognize that if
`they get too much traffic al once, the entire site
`can be brought down and no one will be able to
`visit. Those sites put a limit on the number of
`people who can come to the site at once—that
`way, the site is always available, even if every-
`one who wants to visit can’t get in. If you get this
`”Too Many Users Are Connected” message, it
`usually means that the Web site is up and run-
`ning, but you can’t get in because the maximum
`number of people are already on the site. Keep
`trying—when one person leaves, another can
`come in, and it might be you.
`
`
`
`152
`
`152
`
`
`
`CHAPTER 22 HOW WEB BROWSERS WORK
`
`I39
`
`
`
`Web Server
`
`401 Unauthorized and 403 Forbidden
`
`If
`
`you get either of these error messages,
`you're trying to enter a Web site that
`allows only certain people in—and it’s not
`allowing you to enter. Typically, these
`types of Web sites are password pro-
`tected and also might allow only visitors
`who are from certain domains, such as
`zd.com. If you’ve entered a password,
`you might have entered it improperly, or
`you might not be in a domain that's
`allowed to enter the Web site.
`
`Spinning hourglass This isn’t an error
`message your browser displays—instead,
`your Windows cursor turns into a spinning
`hourglass. The spinning hourglass tells
`you that your browser is trying to make a
`connection to a Web site. if it keeps spin-
`ning and a connection is never made, it
`can mean that an Internet router some-
`
`place between where you are and where
`you're trying to visit has crashed and you
`can’t make the connection. lt can also
`
`mean that you’ve lost your local Internet
`connectioninrsnme reason.
`
`Web Server
`
`
`
` Firewall
`
`404 Not Found When you get this
`message, you’ve arrived at the correct
`Web site, but the specific page you’re
`looking for can’t be found. That spe—
`cific page might have been deleted
`from the site or moved—or you might
`have typed the location incorrectly.
`
`Router
`
`
`Web Server
`
`153
`
`153
`
`
`
`
`
`CHAPTER
`
`23
`
`How Markup
`Languages
`Work
`
`154
`
`154
`
`
`
`W-i'fi'
`
`
` WW5:
`(in: languages are the road signs of a Web page. They are sets of directions that tell the browser
`
`software how to display and manage a Web document, much like written music scores are instructions that
`
`tell a musician how to play a particular song. These instructions (called tags or markups) are embedded in
`
`the source document that creates the Web page.
`
`Tags reference graphic images located in separate files, and they instruct the browser to retrieve and
`
`display these images within the page. Tags can also tell a browser to connect a user to another file or URL
`
`when he clicks an active hyperlink. So each Web page has everything it needs to be displayed on any
`
`computer with a browser that can interpret the markup language.
`
`Your original text will probably have headings, multiple paragraphs, and some simple formatting. A
`
`Web browser will not understand all these layout instructions because the original text isn't formatted
`
`with HTML, the language of the Web (discussed later in this Chapter). Paragraphs, carriage returns,
`
`indents, and multiple spaces will be shown instead as a single space if no HTML markup is added.
`
`Markup languages should not be confused with programming languages, such as C+ or Pascal.
`
`Programming languages are used to write complex applications, such as word processors or spreadsheets.
`
`Markup languages, in contrast, are much simpler and describe the way information should be displayed~
`
`for example, by defining when text should be boldface. In markup languages, tags are embedded within
`
`dOCuments to describe how the documents should be formatted and displayed.
`
`Hypertext Markup Language (HTML) is the markup language of the Web. It defines the format of a
`
`Web document and enables hypertext links to be embedded in the document. You can use any text editor
`
`or word processor to add HTML tags to an ASCII text document, although a number of shareware and
`
`commercially available HTML editors can assist Web page authors as well.
`
`The Web evolves daily, and HTML also expands and changes along with it. The newest changes to
`
`HTML are a group of technologies that together are termed Dynamic HTML (DHTML). These technolo»
`
`gies allow HTML to be more than a static language, and they enable HTML to perform animations and
`become more interactive and flexible.
`
`The eXtended Markup Language (XML) promises to bring even more significant changes to the Web.
`
`It’s dramatically different from other markup languages because it separates the content of a page from its
`
`presentation. Rather than doing things such as giving instructions on text size, it tags different types of
`
`content and then has other technologies such as templates and style sheets determine how that content
`
`should look. For example, if a book were to be presented on the Web, it would tag chapter titles, chapter
`
`numbers, chapter text, and so on. It could then use style sheets to define how chapter titles, chapter numa
`
`bers, and chapter text should look. Doing this means you can build the content of a page once and present
`
`it to many different devices, and in many different ways, withOut doing much extra work.
`
`155
`
`155
`
`
`
`
`
`How HTML Works
`
`0 To display Web pages in any browser, you must add HTML
`lays in your original text. This process is called tagging.
`
`Page Title
`
`
`-
`.
`‘
`, a,
`
`
`dd! 9,- . r file.H‘a’itchnylwlwab_pagelhowitworks.html
`@ #13va Computer @ AppliSubporl ® Apple Store @ M3 MaoTopia ® HSN ©
`expludor @Googlu @cm @mgl @mg @mmml
`
`
`
`
`
`
`
`
`
`n
`der what's happening behind the
`Do you ever WU dive intfl the web?
`screen when YOU
`.ng vwr own Web EltB,
`bout creel:
`ou thought a
`rt?
`masteaiyen't sure where to sta
`
`
`
`but
`
`HTML Links
`
`
`
`
`
`
`
`
`
`Rpm“aimd
`
`
`
`.. zone
`
`156
`
`A
`
`
`
`«Illl
`
`
`
`
`
`156
`
`
`
`
`
`a Use HTML to give your text structure. All HTML
`files begin and end with the HTML tags. Headings
`are marked as such, as are paragraphs, line
`breaks, block quotes, and special character
`emphasis. Any carriage returns or indentations
`within the source text do not affect the browser’s
`display of the page. HTML tags need to be put in
`if they are to be displayed in a browser.
`
`B The finished HTML document will be the
`source page for any browser on any com—
`puter. This simplicity of HTML makes
`cross-platform compatibility easy and reli—
`able. The more complex and specialized
`the HTML tagging, the longer it will take
`to download and display the document.
`
`<html)
`(head)
`<title)l-low The Internet Horksdtitle)
`<
`ead)
`(pita http-equiv="Content-Tupe" contant="text/html; charset=iso-BB§Q-1")
`(body bgcolor="IFFFFFF" link="'665600" vlink=“"556l566">
`(div id="Layeri" stgle="pcsitionzabsolute;
`left:6alpx;
`tom-56px; midthHBBpx; heightl320px; z-index:1"><img src="rack.gif" width=”217" height="372“><fdiv)
`(div id="Lager2” stgle="positionzabsolute;
`leftw;
`topm; width:283px; height:352px; z—Index:2">(img src="rtslde.gif" width="125" height="456“xfdiv)
`(div idel’Lauera" stgle=“posltiontabsolute;
`leftzlafipx;
`topmpx; midtht494px; height:162px; z-index:3")<img src="title.gil" width="545" height="l73")<{oiv>
`ICCCCCC; border: 1px none '8
`(div id-"LageM" stgle="positlonzabsolute;
`left:91px;
`top:1aapx; midth:562px; height2875px; z-indexH; background-color: "000000;
`lager-background-eolor:
`(div id!"Lager5" stule="posltlomabsolute;
`left:5&bpx;
`tapasapx; widthHSb; helght:977px; z-index:5; background-color:
`.FFCCQQ;
`layer-background-color:
`'FFCCQQ; border: 1px none ‘68
`«um id-"Laylnfi" etuie="hnelrinnznhanlute:
`leftrllfipx:
`top:261p><' midthfibgpx; helghufimnx; z-index=5">
`<p><lont size="3” face="Verdana, Flrlal, Helvetlca, sans-serlf"£Do ou ever wonder
`what‘s happening behind the screen uphenlgwdditvei‘mto tthewfifi’l fénifidsfp)
`<p)<font size="3" lace="Verdana, Flrlal, Helvetica, sans-serlf">Have gou thoug‘it
`about creating Hour own Heb slte, but JusL ur'en'l. suie where to stun-tN/fonhfifp.‘
`<p><font size-"3" {ace="Verdana, Flrial, Helvetica, sans-serif">ls the internet
`all magic and madness to you?</font)</p>
`<p)<font slze="3" lace="Verdana, Flrial, Helvetica, sane-serlf”>uell
`than you
`have come to the right placel This Heb site is dedicated to taking the mgsteru
`out of the internet and explaining in clear terms How the Internet Horksldfontxfp)
`<p> < Hp)
`<p><font face-"Verdana, firial, Helvetlca, Ions-serif" slze-"3"><bWou will.
`learn
`about:<fb><.-’font><.u’p>
`(p><b)<font face="Verdana, firial, Helvetica, sans—serif" size="3”><a href=“ptB5_ch2102.html">The
`flnatomg o! a Heb Blte<fa><flont><lb><lp>
`<p><b><font {ace="Verdana, firial, Helvetica, sans-serif”><a hr‘elu“pt91_chalal.html")<font slze="3">The
`architecture of the uebdfontxjwdfentxfb><lp>
`<p><b><font
`lace="Verdana, Flrial, Helvetica, sans-serif"><a hrel="pta7_ch3285.html">(font slze=“3">Emerglng
`Technologies on the uehdrant><Ku><front><fb><fp>
`<p> Up)
`(pront face-"Verdana, Flo-lat, Helvetlca, sans-slrlf")Get ready to SURF!</font></p>
`<p><font faceu'Werdana, Flrlal, Helvetlca, :ans-nril“)fis gou cruise around thls
`site gou will also find lots of hyperlinks to other Bltex all across the Norld
`Hide Heh.</font></p)
`<fdiv>
`top:1QBpx; widthnagpx; heighufialpx; z-index:7">
`lelt:517px;
`(div id!”Lager?" stule="positlon:absolute;
`<p><reht coier=“-999999"><b><ront size="2" face="Verdana, firlal, Helvetlca, sans-lerll'"><a href-"lndex.html"><font column-gagged->Hone<flent><fa><frentx/bx/rentxfp)
`<p><ront color="|'OGQQCC"><a href="intro.html"><b)(font sizevz" face-"Verdana, Flrial, Helvetlca, sans-lerlI">lNTfiDDUCTl0N{/fontX/bxfaxlfontxfp)
`<p)<font color=""999999"><b><font size="2" face="Verdana, firial, Helvetlca, sans-nrll“>PFlHT
`l<br>
`<c: href="ptalstart.html">llhat Is the Internet?(.la)<ffontbeM/lontM/p)
`<p><lont color=“'99€999")<b><font
`size="2" (ace-"Verduna, firlal, Helvetlca, sans-seri{">PfiFlT
`l l<br>
`(a href=“partl25tart.html">The lnternet‘t Underlging Structure<fa><flont><fb><flont)(.r"p)
`<p)<font color=""999999")(b)<font size=”2" facee‘Werdana, firlal, Helvetlca, {ans-eeril">PHRT
`l
`l l<br>
`(a href="par~t935tart.html")Connecting to the Intemetdaxfront><lb></ront></p>
`<p><font color=""999999"><b>(font size="2" faceHWerdana, firlal, Helvetlca, sans-serlf">PfiHT
`IV<bP)
`(a href“‘partB4start.html“>Communicating on the internetda)</ront><fb></ront><fp>
`<p><font colore".999999”><b><font size=“2" {ace-“Verdana, Hrlal, Helvetlca, [ans-serlf">PfiFlT
`V(br>
`(font colorfl"'flfififlcc"><o hrel="partaflstart.html">How the Ndrld Hide Heb Horksdakflontxflontxbe/fontM/p)
`<p><font color="'999999"><b><font slze="2" facee'Werdana, Flrlal, Helvetlca.
`lans-sarlf">FFlFlT
`W (Dr)
`(font color="‘fififificc“)<a hre!="partafistart.html")Common Internet Toolz<fa><ffont><ffoht></b><ffontX/p)
`<p><font color-"‘QOOOQQ")<b)<font sizewl'2" face="Verdana, Flrlal, Helvetlca, sans-serll“)PRHT
`Vll<br>
`(font eoior="~flaoscc"><e href="parta7start.html")l‘lultlmedia on the lntemet<./a)</(ont>(/fant)</b>(r’iant>(.c’p)
`<p><font colore“‘999999"><b><font slze="2” (ac '"Verdanu, Hrlal, Helvetlm, sans-3erlf">FfifiT
`Vl l l<br>
`(font color="“5556CC"><a hre1=“partlastart.html")lntranets and Shopping on
`the Intametdax/ront></ront></b><frent><fp>
`<p><font color=""999999")<b><font size="2“ 1ace="Verdana, Flrial, Helvetica, sans-serif">PFIFlT
`|X<br>
`(font color="'66660l3"><a href="purl:ogstart.html">8afeguarding the lnternet</a)<!font}(/fant></b></font><i'p>
`<p><font color="‘999999“)<b><lont slzeu”2" Iace=“Verdana, Hrial, Helvetica. sans-serif"><a href=”Index.html"><font color="'BBBlB8">Fleturn
`to (hr)
`1mm of mnrnni-adfontx/aéqront,»<,/b><,rreht><.a‘p>
`<p)&hbsp;<f >
`<p> < p)
`<fdiv>
`(div id-“LagarB” stule="ppsl‘tion:absolute;
`(div id=“Lauer9" stgle="poxitlontabsolute;
`(div idI"Lager18" stgle="poeltio
`blolute;
`
`<
`only)
`<%v id-“Lauerll” 5tgle="pasltior .absalute;
`(fhtml)
`
`left:351px;
`left:12Bpx;
`left:2159x;
`left1512px;
`
`top:350px; midthlepr; heightil32px; z-index:9")<img src="bot.gi(" width="151" height="154"><fdiv)
`
`top:622px; uidtht77px; height:89px; z-index:9”><a href="map.html“)(img sr
`"map.gif" width="63" height="83" border="B"></a><fdi
`top:523px; widtthpx; height:76px; z-index:16“><a hre!="searchHIll.html")<img src="search.gll" width="83" height="93" border=‘
`top:522px1 width:6?px; heighttlelpx; z-index:11")<a href="helpme-html"><img src="help.gif" width=“83" height="83" border="6"»
`
`Title
`Ill-III-IIIIIIl-IIIIII-
`
`Graphic
`
`Graphic
`
`Text
`
`
`
`Hyperlinks
`
`w G
`
`raphic
`Hyperlink
`
`[I Most Web browsers enable your document to retain its structural integrity when you display, or parse,
`it. Headings will appear in a larger font size than text within paragraphs, for example, and block quotes
`will be uniformly indented. However, the look might vary from browser to browser. Note that browsers
`determine the exact font, size, and color. Also be aware that the relative importance of the elements is
`always kept intact.
`
`157
`
`157
`
`
`
`
`
`
`
`How Dynamic HTML Works
`
`Dynamic HTML (DHTML) differs from traditional HTML in that it enables Web pages to be
`changed on-the-fly, after they’ve been downloaded. In plain HTML, after a page is down-
`loaded, it is static and can be changed only when a user takes an action of some kind. But
`DHTML, for example, could cause an animation of a rocket to fly across your browser win-
`dow several seconds after the page has been downloaded—without your doing anything.
`
`.
`
`._
`
`-- —-
`
`_
`
`.
`
`_ Rflflgf€lt
`.5 6267166 /
`
`.
`
`'
`
`.
`
`.
`
`'
`
`_
`
`'
`
`_-
`
`" .,
`
`Welcome to «kn
`internation;
`home rocke
`club!
`
`p
`
`ROCKET SCIENCE
`
`Welcome to the international homc rocketry club!
`
`gum HERE TO LEARN Mom
`
`Q ‘6.
`
`'li
`
`
`page itself.
`
`a DHTML does its work without having
`to contact the server after the page
`downloads, so it can perform some
`interactive functions more quickly
`than other technologies that have to
`contact the server. The instructions
`
`for performing the commands are in
`the HTML commands that are in the
`
`158
`
`
`
`158
`
`
`
`CHAPTER 23 HOW 'MARKUP LANGUAGES WORK
`
`I45
`
`3 Although DHTML is often referred to as if it were a single technology, it is, in fact, a general term used
`for a group of technologies that can work together or by themselves to change a Web page after the
`page has been downloaded to your computer. These technologies are the Document Object Model
`(DOM), Cascading Style Sheets (CSS), and client-side scripting languages, such as JavaScript.
`
`Elements of DHTML
`
`Plain HTML
`
`Dynamic HTML
`
`Document Object Model (DOM)
`
`.
`
`#
`
`How
`
`lv)vHTll:IL
`
`or s
`
`HDngML
`
`-
`
`!.-»
`
`.
`
`n The DOM defines every object and element on a Web page and enables those objects to be manipulated
`or accessed. This includes fonts, graphics, tables, and visual elements, as well as elements you can‘t
`necessarily see, such as the browser's version number and the current date and time. Without DOM, all
`the elements on a page are static. So on the simplest level, DHTML could use the DOM to change the
`font of every letter, individually, on a Web page.
`
`Cascading Style Sheet
`
`3
`
`Plain HTML
`
`Dynamic HTML
`
`How
`DHTML
`
`Works
`
`E Cascading Style Sheets are, in essence, templates that apply formatting and style information to the
`elements of a Web page. They're called cascading because any single page can have more than one
`style sheet associated with it. Additionally, Cascading Style Sheets enable images to overlap one
`another. This enables animations to be created easily on a page.
`
`Plain HTML
`
`Dynamic HTML
`
`o
`o
`o
`0
`Cllent-Slde Scrlptmg
`
`" Haw
`’evlgmsl-
`
`:
`4
`
`.
`
`i
`How
`whilst.
`
`a Client-side scripting languages perform much of the work of DHTML. These languages access the DOM
`and manipulate its elements, and they do the same to Cascading Style Sheets. They perform the actions
`of DHTML. So a script, for example, could turn a word a different color when a mouse moves across it,
`or it could create easy—to-use collapsible navigation on every page on a Web site.
`
`159
`
`159
`
`
`
`
`
`How XML Works
`
`XML solves several a major
`problems for Web develnp-
`ers. Without it, to deliver
`Web pages to different
`devices such as computers,
`cell phones, and wireless
`Palm devices, a developer
`must create and maintain
`
`three separate Web sites,
`with special coding for each
`device—HTML for the com-
`
`_
`
`HTML
`
`Web Clipping
`
`n
`'
`
`,
`
`‘
`.
`
`l
`
`I
`
`I
`
`puter, WAP for the cell
`phone, and what's called
`Web clipping for the wireless
`
`Palm devices. It’s an expen-
`
`sive, difficult, and time-
`consuming proposition. And
`even if a developer is build—
`ing a site only for computers,
`every time the design
`changes, all the pages must
`be receded—again, an
`expensrve and Wm?
`consuming proposrtion.
`
`<Sale flyer>
`<0lfer>Get it While it's HoI!</0ller>
`<Promotional Copy>
`You can’t miss this one!
`One-time offer only —
`gaming synems at prices
`you wn’t believe! <IPmnwtional Copy>
`<Product>Sony PlayStations<lProduct>
`<Price> $l59.95<ll’rice>
`Sale ends <End Dale> l'lay l5
`
`
`
`
`
`Handheld
`
`’
`
`Cellular
`Telephone
`
`
`
`WAP
`
`E With XML, a developer can create the Web site just once.
`Then it can be automatically formatted to several types of
`devices, such as Internet—connected computers, wireless
`Palm devices, and cell phones using WAP. And even if
`the site is being built for only
`computers, when there is a
`redesign, with XML, all the
`pages need not be rebuilt.
`
`'
`
`:
`r
`
`-
`
`qm Datg>
`XML
`
`%
`"r-f/ ’SLT
`f
`B The most important concept to understand about XML is that the language is used only to convey informa-
`tion about content, not about the presentation of the content. So, for example, it doesn’t give instructions
`on what size text should be. But it uses tags to define the type of content on the page. Then it uses other
`techniques, as you'll see in the next steps, to display those pages. in that way, a single page can be dis—
`played many different ways, without having to go back and alter the original page—only the designs, which
`are separate from the content, need to be changed.
`
`160
`
`160
`
`
`
`a After the site knows what kind of device is visiting, it
`takes the XML, and using XSLT, changes it into the
`proper format—for example, a WAP document that
`the cell phone can view with its WAP microbrowser
`or an HTML document for a computer.
`
`
`
`‘Vfi-fflafldhad.
`
`Who- are viii?
`
`Here is your clipped Web parge.
`
`
`
`
`
`I’m a cellular phone.
`
`B When a device visits a site built with XML, there
`needs to be some way for site to know what type of
`device it is—— a computer, for example, or a cell
`phone. Common Gateway Interface (CGl) scripts can
`detect which device is contacting the site.
`
`Who are you.
`
`Here is your WAP.
`
` 1
`
`her it Winn; i'r'b law!
`
`You can't miss this one!
`One—time offer only ..
`gaming systems at
`prices you won’t believe!
`
`iI
`
`HTML
`
` Sale ends Ma! I5
`HTML document with a different design.
`
`When XML content is posted on a Web
`site, different designs need to be applied
`to that content so that it can be viewable
`
`by devices connecting to it—for example,
`cell phones. eXtensible Style Language
`Transformations (XSLT) can be applied to
`the XML. XSLI can take XML and apply
`different designs to it or change it to
`other forms of XML—for example, it can
`take the XML and turn it into a WAP page
`that can be viewed by a cell phone and
`take the same XML and turn it into a
`
`161
`
`161
`
`
`
`
`
`CHAPTER
`
`How Hypertext
`Works
`
`—.mun—n.
`...m....u—awu
`m
`J“.
`274“"«w... om ww“.m“""u
`mm...”-
`-wu‘u-..
`.. an»... u...»
`.15....mu m
`
`
`7—“
`~u. ... pm.“ mfilvlyluli
`mw—‘w a... Int—mug
`
`. 1w
`
` "am...“an...”
`
`it-u-vlw-‘nl-ImhhMM
`
`numb-um
`
`
`iti: 5
`
`nmnmmmmv.
`manna-mum
`nuwmmwnmqn
`.mY-I~D~U
`I‘D-“J‘Idnfl-Ipn
`nun-um mandamus-unwan-
`sun-ma mmmdhm-fl
`“autumn-hum
`
`162
`
`whoa—u”..-
`
`m- Inh-
`
`3??if
`
`162
`
`
`
`IN the late 19605, a computer scientist named Ted Nelson introduced hypertext, a concept that lays the
`
`foundation for the World Wide Web and its connections between documents, or pages.
`
`Nelson wanted to create a new way of exploring information. He wanted to provide the reader with a
`
`spontaneous means of accessing more and more in—depth information about something that sparked the
`
`reader’s interest when reading text on the page. Rather than reading a document from beginning to end,
`
`digesting the material in a sequential order, the reader could highlight a word and receive more information
`
`on the meaning of that word, for example.
`
`Nelson imagined that you could read the United States Constitution, come across the term “electoral
`
`college,” and then open another document that explains how the electoral college works. From that docu—
`
`ment, you might open another document that lists the votes of the electoral college from its founding to the
`
`present. From there, you might choosc to open a document about William Jefferson Clinton, then another
`
`about the First Cat, Socks, then another about the care and feeding of felines, and so forth. Ultimately, you
`
`could find a subject that wasn’t even remotely connected to the Constitution, but which you would find
`
`interesting or entertaining.
`
`This hypertext concept was obviously on Tim Berners—Lee’s mind when he began thinking about how
`
`researchers could share their work across the Internet. He envisioned a system in which a document could
`
`be linked to other documents, enabling researchers to easily find more and related information simply by
`
`following a link from one document on the network to another.
`
`Typically, hypertext consists of a hyperlink that appears onscreen as a highlighted word, icon, or graphic.
`
`By moving a mouse cursor over the item, or object, and clicking it, you easily navigate to additional infor»
`
`mation. On the Web, that information can be located at any other place on the Web, be it on the same host
`
`server or one across the globe. A linked object can be various media, such as text (linking from one charac—
`
`ter to a whole document, for example), a graphical button (such as direction arrows that move from page to
`
`page), or still images (photos, icons, or a comic strip), for example. The documents and objects that are
`
`being linked to can be on the same site as the original document or on an entirely different site.
`
`Hypertext links are embedded into a Web document using Hypertext Markup Language (HTML). A
`
`text link usually appears onscreen as an underlined word or phrase and is sometimes rendered in a different
`
`color from other text, depending on how your Web browser interprets the HTML codes. When you place
`the mouse cursor on this underlined text and click the mouse button, you initiate a request by the browser
`
`for a new Web page or—if the text references an internal link to information in the same document—direct
`
`your browser to scroll to another, specific point within the same document.
`
`Images or icons can also act as hyperlinks. When you move the mouse cursor over the icon or graphic
`
`and click the mouse button, you launch the request to retrieve the linked information.
`
`163
`
`163
`
`
`
`
`
`
`mummmm '
`hmmmmmmw‘nh‘
`gamut-unwind
`hmmJ-‘Mw—IEM’
`mmmmmhmmmlmw‘sm
`hmmmmmnmmmw
`
`”Mahayana-mm
`mnfibdlm
`
`
`
`
`umummmmmwh
`www.mmumhmnn
`mam
`
`
` Mama—nun.»
`m...
`'3” targéET’N’art 3
`
`The "hyperlinking" begins when you
`first retrieve a Web page from a remote
`Web server. Target links within the page
`move you quickly from one part of the
`page to the next.
`
`
`
`
`
`
`mmama». mam-MM»
`hMacnwwln—‘w
`
`
`
`
`
`
`
`
`164
`
`164
`
`
`
`a A relative link is used to initiate a request by your
`Web browser to retrieve a page located on the same
`Web server as the page from which you are linking. Web
`developers use relative links when they’re pointing to a page under
`their control because this enables the to more easily maintain their
`HTML coding if their server locations change.
`
`<a href="loursitelrelativelchapter_4.html">Chapter 4<Ia>
`‘7
`'
`
`mama-let
`Wlmlfilmmhlmm'v
`UmkdyiugAlrhila'lm
`
`
`
`
`
`
`"gnaw-muniti-
`
`‘*~.\..~u.a.~.
`
`“a....m
`
`4....—
`
`
`<a href="/oursite/relative/chapter_7.html">Chapter 7<la>
`
`flow lnlnnet l-‘du'l‘yw Wonk
`
`a A hyperlink that leads to a
`completely different Web
`server uses an absolute link.
`
`Because these links might not
`be under the control of the
`
`Web developer who created
`the page, there is a chance that
`this will be a ”dead link"—the
`
`page will have been moved
`without the Web developer
`knowing about it.
`
`
`
`
`
`
`
`
`
`lain—vi”rd-I! ‘ hid ml - Manna. AW Mimi!“ Brim 5pm!
`
`uwmmwnmmmnmmm.
`m a Humlnmgl
`Nm g MM;
`in m. Illn-
`gunlnm 5 gggngmy
`Run-flan a sauna
`-W
`mmmm.
`mm" Am. M... —|‘
`alumm
`com
`r- a. Imam mm
`mm
`E5
`.(mm- hm
`Inn-ulna
`"mm M
`_Ih‘h
`b".
`Wm. WWW"
`»Cun--M¢-¢vwamu
`.
`.
`.
`..
`.
`_ .
`
`<a href=www.yahoo.com><img src="searchyahoo.gif"><Ia>
`
`165
`
`165
`
`
`
`
`
`
`
`,n.
`m .
`nnnnnnnnn
`''''''
`
`166
`
`166
`
`
`
`TH E Web pages and the hosts that make up the World Wide Web must have unique locations so that your
`
`computer can locate and retrieve the pages. The unique identifier for a host is called the Internet Protocol
`
`(IP) address, and the unique identifier for a page is called the uniform resource Iocator (URL). A URL
`
`functions much like a postal or email address. Just as postal and email addresses list a name and specific
`
`location, a URL, or Web address, indicates where the host computer is located, the location of the Web site
`
`on the host, and the name of the Web page and the file type of each document, among other information.
`
`A typical URL looks like this:
`http : / /www. zdpress . com/internetwor‘ks/ index . html/
`
`If you were to interpret the instructions in this URL from left to right, it would translate to: “Go to the
`
`host computer called zdpr‘ess (a commercial business), in a directory called intor‘networ‘ks, and retrieve a
`
`hypertext document with the filename index. html.” The URL, or address, tells the browser which docu’
`
`ment to fetch and exactly where to find it on a specific remote host computer somewhere on the Internet.
`
`The first part of the URL indicates what type of transfer protocol will be used to retrieve the specified
`
`document. The most common request is for a hypertext document that uses Hypertext Transfer Protocol
`
`(HTTP).
`
`The second portion of the URL refers to the specific host computer on which the document resides,
`
`which is to be contacted by the browser software. This part of the address is also called the domain name.
`
`See Chapter 5, “How Internet Addresses and Domains Work,” for more information about domains.
`
`The third part of the URL is the directory on the host computer that contains a specific Web site or
`
`multiple Web sites. This is always located after the first single slash in the URL and is essentially the sub—
`
`directory on the hard disk that houses the Web site. Subdirectories might also be indicated in this part of
`
`the address. For example, if the previous URL were changed to http: //www. zdpress . com/
`
`internetworks/partone/chapters/chapte.html there would be two subdirectories—par‘t one and chapters.
`
`In the preceding example, the filename is chapte . html. This is always the last portion of the URL. If
`
`you see an address without a filename, it is assumed that the filename index . html contains the requested
`
`Web page. Therefore, the default document a Web server will deliver to the client when no o
Accessing this document will incur an additional charge of $.
After purchase, you can access this document again without charge.
Accept $ Charge
Still Working On It
This document is taking longer than usual to download. This can happen if we need to contact the court directly to obtain the document and their servers are running slowly.
Give it another minute or two to complete, and then try the refresh button.
A few More Minutes ... Still Working
It can take up to 5 minutes for us to download a document if the court servers are running slowly.
Thank you for your continued patience.
This document could not be displayed.
We could not find this document within its docket. Please go back to the docket page and check the link. If that does not work, go back to the docket and refresh it to pull the newest information.
Your account does not support viewing this document.
You need a Paid Account to view this document. Click here to change your account type.
Your account does not support viewing this document.
Set your membership
status to view this document.
With a Docket Alarm membership, you'll
get a whole lot more, including:
- Up-to-date information for this case.
- Email alerts whenever there is an update.
- Full text search for other cases.
- Get email alerts whenever a new case matches your search.
One Moment Please
The filing “” is large (MB) and is being downloaded.
Please refresh this page in a few minutes to see if the filing has been downloaded. The filing will also be emailed to you when the download completes.
Your document is on its way!
If you do not receive the document in five minutes, contact support at support@docketalarm.com.
Sealed Document
We are unable to display this document, it may be under a court ordered seal.
If you have proper credentials to access the file, you may proceed directly to the court's system using your government issued username and password.
Access Government Site
