The use of <var> or {{var}} is preferred to simply italicizing for many reasons, including accessibility, separation of presentation and content, semantic Web, and metadata. In XHTML and HTML, the <var> element has semantic meaning, while simple italicization does not. This template provides a tiny hint of kerning to compensate for the italicization and enhance readability.
"Variable" in this sense may include arbitrary or unknown names or terms, examples of human input, arithmetical variables in equations, etc. This template (and the underlying XHTML) are generally not used if MediaWiki's <math>...</math> tags (or any other stand-alone mathematical markup) are being used.
At times, you may wish to use a serif font. This is especially true when attempting to render single-letter variables like "I" (upper-case "i") and "l" (lower-case "L"), since they are nearly indistinguishable (if at all). In such situations, use the {{varserif}} template instead of {{var}}, to make them more distinguishable, like these serif examples: I, l.
Examples
Wikitext
HTML
Renders as
{{var|username}}
<var>username</var>
username
Markup
Renders as
<var>username</var>
username
{{var|username}}
username
The commandline should read: {{samp|%}} {{kbd|1=ssh {{var|hostname}}}}<br />(where {{var|hostname}} is the IP address or ...)<br />If it is correct, press {{key press|Enter}}
The commandline should read: %ssh hostname (where hostname is the IP address or ...) If it is correct, press ↵ Enter
in this equation, let {{var|x}}{{=}}1 and {{var|y}}{{=}}120 ...
To indicate text is a variable name. Use for any variable names except those including "I" (uppercase i) and/or "l" (lowercase L); for these, {{var serif}} should be used to ensure a noticeable distinction
To display parameters as used in code (i.e. with triple braces), especially to indicate relationships between them. May be combined with {{parameter}} above
To display parameter values lightly bordered; replaces <code>...</code>, especially when value contains embedded or leading/trailing blanks; visualized here with middot (·) but can use ␠, ▯, or any character.
To indicate text is source code. To nest other templates within {{code}}, use <code>...</code>. {{codett}} differs only in styling: someMethod becomes someMethod
( or {{dc}}) To indicate deprecated source code in template documentation, articles on HTML specs, etc. The {{dc2}} variant uses strike-through (<blink>) while {{dcr}} uses red (<blink>).
