The [[MediaWiki]] software, which drives Wikipedia, allows the use of a subset of [[HTML 5]] [[HTML element|elements]], or tags and their [[HTML attribute|attributes]], for presentation formatting.{{r|sanitizer}} ButHowever, most HTML functionality can be included byreplicated using equivalent [[Help:Wiki markup|wiki markup]] or [[Help:TemplateTemplates|templates]];. theseThese alternatives are generally preferred within articles,asbecause they are sometimesoften simpler for most editors to use and less intrusive in the editing window; butinterface. [[Wikipedia:Manual_of_Style#Keep_markup_simple|Wikipedia's Manual of Style]] recommends theirwhen useand inwhere these certainalternatives casesshould be used. (See [[Help:Wikitext]] for wiki equivalents to HTML tags not otherwise discussed below.) And HTML is useful outside of articles, for example for formatting within templates. For help with Cascading Style Sheet use within Wikipedia see [[Help:Cascading Style Sheets]].
HTML can also be useful outside articles, such as for formatting within templates. For assistance with using Cascading Style Sheets on Wikipedia, see [[Help:Cascading Style Sheets]].
Some tags look like HTML, but are actually MediaWiki [[#Parser and extension tags|parser and extension tags]], and so are really wiki markup. HTML in pages can be checked for HTML5 compliance by using [[#Validation|validation]]. Some elements and attributes are supported by MediaWiki and browsers, but have been [[Wikipedia:HTML5|deprecated by HTML5]], and therefore should no longer be used.▼
▲Some tags lookthat likeresemble HTML, but are actually MediaWiki [[#Parser and extension tags|parser and extension tags]], and so are reallyactually wiki markup. HTML included in pages can be checkedvalidated for HTML5 compliance by using [[#Validation|validation]]. SomeNote that some elements and attributes are supported by MediaWiki and browsers, but have been [[Wikipedia:HTML5|deprecated by HTML5]], and therefore should no longer be used.{{TOC limit|3}}
