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€paragraph€tags.Ì€€€Ì€€€€Numbered€ListsÌ€€€€Ì€€€Ì€€€Ì€€€A€numbered€list€(also€called€an€ordered€list,€from€which€the€tag€nameÌ€€€derives)€is€identical€to€an€unnumbered€list,€except€it€uses€
€paragraph€tags),€lists,€or€other€definition€information.Ì€€€Ì€€€€Nested€ListsÌ€€€€Ì€€€Ì€€€Ì€€€Lists€can€be€arbitrarily€nested,€although€in€practice€you€probablyÌ€€€should€limit€the€nesting€to€three€levels.€You€can€also€have€a€numberÌ€€€of€paragraphs,€each€containing€a€nested€list,€in€a€single€list€item.Ì€€€Ì€€€An€example€nested€list:ÌÌ€€€€
€tag€(which€stands€for€``preformatted'')€to€generate€textÌ€€€in€a€fixed-width€font€and€cause€spaces,€new€lines,€and€tabs€to€beÌ€€€significant.€(That€is,€multiple€spaces€are€displayed€as€multipleÌ€€€spaces,€and€lines€break€in€the€same€locations€as€in€the€source€HTMLÌ€€€file.)€This€is€useful€for€program€listings.€For€example,€the€followingÌ€€€linesÌÌ€€€€Ì€€€€€€#!/bin/cshÌ€€€€€€cd€$SCRÌ€€€€€€cfs€get€mysrc.f:mycfsdir/mysrc.fÌ€€€€€€cfs€get€myinfile:mycfsdir/myinfileÌ€€€€€€fc€-02€-o€mya.out€mysrc.fÌ€€€€€€mya.outÌ€€€€€€cfs€save€myoutfile:mycfsdir/myoutfileÌ€€€€€€rm€*Ì€€€€ÌÌ€€€Ì€€€Ì€€€display€asÌÌ€€€€€€#!/bin/cshÌ€€€€€€cd€$SCRÌ€€€€€€cfs€get€mysrc.f:mycfsdir/mysrc.fÌ€€€€€€cfs€get€myinfile:mycfsdir/myinfileÌ€€€€€€fc€-02€-o€mya.out€mysrc.fÌ€€€€€€mya.outÌ€€€€€€cfs€save€myoutfile:mycfsdir/myoutfileÌ€€€€€€rm€*ÌÌ€€€Ì€€€Ì€€€Hyperlinks€can€be€used€within€€sections.€You€should€avoid€usingÌ€€€other€HTML€tags€within€€sections,€however.Ì€€€Ì€€€Note€that€because€<,€>,€and€&€have€special€meaning€in€HTML,€you€haveÌ€€€to€use€their€escape€sequences€(<,€>,€and€&,€respectively)€toÌ€€€enter€these€characters.€See€the€section€Special€Characters€for€moreÌ€€€information.Ì€€€Ì€€EXTENDED€QUOTATIONSÌ€€Ì€€€Ì€€€Ì€€€Use€the€€tag€to€include€quotations€in€a€separate€block€onÌ€€€the€screen.€Most€browsers€generally€indent€to€separate€it€fromÌ€€€surrounding€text.Ì€€€Ì€€€An€example:ÌÌ€€€€Ì€€€€I€still€have€a€dream.€It€is€a€dream€deeply€rooted€in€theÌ€€€€American€dream.€ÌÌ€€€Ì€€€Ì€€€The€result€is:Ì€€€Ì€€€€€I€still€have€a€dream.€It€is€a€dream€deeply€rooted€in€the€AmericanÌ€€€€€dream.Ì€€€€€Ì€€€€€I€have€a€dream€that€one€day€this€nation€will€rise€up€and€live€outÌ€€€€€the€true€meaning€of€its€creed.€We€hold€these€truths€to€beÌ€€€€€self-evident€that€all€men€are€created€equal.Ì€€€€€Ì€€ADDRESSESÌ€€Ì€€€Ì€€€Ì€€€The€€tag€is€generally€used€to€specify€the€author€of€aÌ€€€document€and€a€means€of€contacting€the€author€(e.g.,€an€emailÌ€€€address).€This€is€usually€the€last€item€in€a€file.Ì€€€Ì€€€For€example,€the€last€line€of€the€online€version€of€this€guide€isÌÌ€€€€Ì€€€€A€Beginner's€Guide€to€HTML€/€NCSA€/€pubs@ncsa.uiuc.eduÌ€€€€ÌÌ€€€Ì€€€Ì€€€The€result€isÌ€€€€A€Beginner's€Guide€to€HTML€/€NCSA€/€pubs@ncsa.uiuc.eduÌ€€€€Ì€€€Ì€€€Ì€€€NOTE:€€is€not€used€for€postal€addresses.€See€``ForcedÌ€€€Line€Breaks''€on€page€10€to€see€how€to€format€postal€addresses.Ì€€€ÌCharacter€FormattingÌÌ€€€Ì€€€Ì€€€You€can€code€individual€words€or€sentences€with€special€styles.€ThereÌ€€€are€two€types€of€styles:€logical€and€physical.€Logical€styles€tag€textÌ€€€according€to€its€meaning,€while€physical€styles€specify€the€specificÌ€€€appearance€of€a€section.€For€example,€in€the€preceding€sentence,€theÌ€€€words€``logical€styles''€was€tagged€as€a€``definition.''€The€sameÌ€€€effect€(formatting€those€words€in€italics),€could€have€been€achievedÌ€€€via€a€different€tag€that€specifies€merely€``put€these€words€inÌ€€€italics.''Ì€€€Ì€€PHYSICAL€VERSUS€LOGICAL:€USE€LOGICAL€STYLES€WHEN€POSSIBLEÌ€€Ì€€€Ì€€€Ì€€€If€physical€and€logical€styles€produce€the€same€result€on€the€screen,Ì€€€why€are€there€both?€We€devolve,€for€a€couple€of€paragraphs,€into€theÌ€€€philosophy€of€SGML,€which€can€be€summed€in€a€Zen-like€mantra:€``TrustÌ€€€your€browser.''Ì€€€Ì€€€In€the€ideal€SGML€universe,€content€is€divorced€from€presentation.Ì€€€Thus,€SGML€tags€a€level-one€heading€as€a€level-one€heading,€but€doesÌ€€€not€specify€that€the€level-one€heading€should€be,€for€instance,Ì€€€24-point€bold€Times€centered€on€the€top€of€a€page.€The€advantage€ofÌ€€€this€approach€(it's€similar€in€concept€to€style€sheets€in€many€wordÌ€€€processors)€is€that€if€you€decide€to€change€level-one€headings€to€beÌ€€€20-point€left-justified€Helvetica,€all€you€have€to€do€is€change€theÌ€€€definition€of€the€level-one€heading€in€the€presentation€device€(i.e.,Ì€€€your€World€Wide€Web€browser).Ì€€€Ì€€€The€other€advantage€of€logical€tags€is€that€they€help€enforceÌ€€€consistency€in€your€documents.€It's€easier€to€tag€something€as€Ì€€€€I€have€a€dream€that€one€day€this€nation€will€rise€up€andÌ€€€€live€out€the€true€meaning€of€its€creed.€We€hold€these€truthsÌ€€€€to€be€self-evident€that€all€men€are€created€equal.€
Ì€€€€
Ì€€€than€to€remember€that€level-one€headings€are€24-point€bold€Times€orÌ€€€whatever.€The€same€is€true€for€character€styles.€For€example,€considerÌ€€€the€€tag.€Most€browsers€render€it€in€bold€text.€However,€it€isÌ€€€possible€that€a€reader€would€prefer€that€these€sections€be€displayedÌ€€€in€red€instead.€Logical€styles€offer€this€flexibility.Ì€€€Ì€€€€Logical€StylesÌ€€€€€for€a€word€being€defined.€Typically€displayed€in€italics.€(NCSAÌ€€€€€€€€€€Mosaic€is€a€World€Wide€Web€browser.)Ì€€€€€€for€emphasis.€Typically€displayed€in€italics.€(Watch€out€forÌ€€€€€€€€€€pickpockets.)Ì€€€Ì€€€€€€€€€€for€titles€of€books,€films,€etc.€Typically€displayed€inÌ€€€€€€€€€€italics.€(A€Beginner's€Guide€to€HTML)Ì€€€
Ì€€€€€€€€€€for€snippets€of€computer€code.€Displayed€in€a€fixed-width€font.Ì€€€€€€€€€€(The€
€header€file)Ì€€€€€for€user€keyboard€entry.€Should€be€displayed€in€a€boldÌ€€€€€€€€€€fixed-width€font,€but€many€browsers€render€it€in€the€plainÌ€€€€€€€€€€fixed-width€font.€(Enter€passwd€to€change€your€password.)Ì€€€Ì€€€€€€€€€€for€computer€status€messages.€Displayed€in€a€fixed-width€font.Ì€€€€€€€€€€(Segmentation€fault:€Core€dumped.)Ì€€€Ì€€€€€€€€€€for€strong€emphasis.€Typically€displayed€in€bold.€(Important)Ì€€€€€for€a€``metasyntactic''€variable,€where€the€user€is€to€replaceÌ€€€€€€€€€€the€variable€with€a€specific€instance.€Typically€displayed€inÌ€€€€€€€€€€italics.€(rm€filename€deletes€the€file.)Ì€€€€€€€€€€Ì€€€€Physical€StylesÌ€€€€€€€bold€textÌ€€€€€€€italic€textÌ€€€€€€typewriter€text,€e.g.€fixed-width€font.Ì€€€€€€€€€€Ì€€USING€CHARACTER€TAGSÌ€€Ì€€€Ì€€€Ì€€€To€apply€a€character€style,Ì€€€€1.€Start€with€ ,€where€tag€is€the€desired€character€formattingÌ€€€€€€€tag,€to€indicate€the€beginning€of€the€tagged€text.Ì€€€€2.€Enter€the€tagged€text.Ì€€€€3.€End€the€passage€with€ .Ì€€€€€€€Ì€€SPECIAL€CHARACTERSÌ€€Ì€€€€Escape€SequencesÌ€€€€Ì€€€Ì€€€Ì€€€Four€characters€of€the€ASCII€character€set€--€the€left€angle€bracketÌ€€€(<),€the€right€angle€bracket€(>),€the€ampersand€(&)€and€the€doubleÌ€€€quote€(")€--€have€special€meaning€within€HTML€and€therefore€cannot€beÌ€€€used€``as€is''€in€text.€(The€angle€brackets€are€used€to€indicate€theÌ€€€beginning€and€end€of€HTML€tags,€and€the€ampersand€is€used€to€indicateÌ€€€the€beginning€of€an€escape€sequence.)Ì€€€Ì€€€To€use€one€of€these€characters€in€an€HTML€document,€you€must€enter€itsÌ€€€escape€sequence€instead:Ì€€€<€€€the€escape€sequence€for€<Ì€€€>€€€the€escape€sequence€for€>Ì€€€&€€the€escape€sequence€for€&Ì€€€"Ì€€€€€€€€€€the€escape€sequence€for€"Ì€€€€€€€€€€Ì€€€Ì€€€Ì€€€Additional€escape€sequences€support€accented€characters.€For€example:Ì€€€öÌ€€€€€€€€€€the€escape€sequence€for€a€lowercase€o€with€an€umlaut:€