It is useful for programming advanced templates, and is often used within a template to the right of an equals sign. It may also be used in a template to disambiguate parsing of braces.

It can also be used to temporarily disable code. Unlike "commenting out" using HTML <!-- -->, it nests. This means that {{void|foo {{void|bar}} baz}} is valid, whereas <!-- foo <!-- bar --> baz --> will produce baz -->.

It provides a particularly concise way of temporarily disabling templates, by prefixing the template name with ^|, making the template name become the (ignored) first unnamed parameter. For example, suppose you have a page {{Under construction}} for several days, and wish to change that to {{In use}} during active editing sessions. Rather than delete the unused template, you can leave both templates in the wikitext and change from {{^|In use|...}}{{Under construction|...}} to {{In use|...}}{{^|Under construction|...}}.

Another possible application would be to temporarily disable an infobox on an article page while a problem with the infobox template itself is resolved.

A deeper no-op is {{subst:void|foobar}} or {{subst:^|foobar}}. It disappears completely upon saving.

{{Null}} also redirects here. It is also possible to use {{ns:0}}, the empty/void/null string for the main namespace.

It can be used in place of <nowiki /> to break character sequence parsing, for example {{nowrap|{''a''}{{null}}}} to force the first closing brace to be treated as part of the template parameter instead of as the end of the template expression.

• {{0}}
• Template:Nothing – a template that displays an invisible HTML tag
• Template:Text – a template that just displays its first parameter unchanged.