This a simple helper template, to be used in other templates. It displays a link to a category if that category exists; otherwise it just displays plaintext.

An optional display text may be added as a second parameter

{{LinkCatIfExists|CategoryName|OptionalDisplayText}}

Simple usage
{{LinkCatIfExists|CategoryName}}
Examples:
With optional display text
{{LinkCatIfExists|CategoryName|DisplayText}}
Examples: