alt — A text-only annotation, often used for accessibility
A text (or other nonvisual) description of a graphical element. This is intended to be an alternative to the graphical presentation.
May be formatted inline or as a displayed block, depending on context. Sometimes suppressed.
These elements contain alt: abbrev, accel, acronym, address, application, arg, artpagenums, attribution, authorinitials, bibliocoverage, biblioid, bibliomisc, bibliomset, bibliorelation, bibliosource, bridgehead, citation, citebiblioid, citetitle, city, classname, classsynopsisinfo, code, command, computeroutput, confdates, confnum, confsponsor, conftitle, constant, contractnum, contractsponsor, contrib, country, database, edition, email, emphasis (db._emphasis), emphasis (db.emphasis), entry, envar, equation, errorcode, errorname, errortext, errortype, exceptionname, fax, filename, firstname, firstterm, funcdef, funcparams, funcsynopsisinfo, function, glosssee, glossseealso, glossterm, guibutton, guiicon, guilabel, guimenu, guimenuitem, guisubmenu, hardware, holder, honorific, html:button, html:label, html:legend, informalequation, informaltable (db.cals.informaltable), initializer, inlineequation, inlinemediaobject, interfacename, issuenum, jobtitle, keycap, keycode, keysym, label, lineage, lineannotation, link, literal, literallayout, manvolnum, markup, mathphrase, mediaobject, member, methodname, modifier, mousebutton, msgaud, msglevel, msgorig, olink, option, optional, orgdiv, orgname, otheraddr, othername, package, pagenums, para, paramdef, parameter, personname, phone, phrase (db._phrase), phrase (db.phrase), pob, postcode, primary, primaryie, productname, productnumber, programlisting, prompt, property, publishername, quote, refdescriptor, refentrytitle, refmiscinfo, refname, refpurpose, releaseinfo, remark, replaceable, returnvalue, revnumber, revremark, screen, secondary, secondaryie, see, seealso, seealsoie, seeie, seg, segtitle, seriesvolnums, shortaffil, simpara, state, street, subscript, subtitle, superscript, surname, symbol, synopsis, systemitem, table (db.cals.table), tag, td, term, termdef, tertiary, tertiaryie, th, title, titleabbrev, tocentry, token, trademark, type, uri, userinput, varname, volumenum, wordasword, year.