الگو:Category
از ویکیپدیا، دانشنامهٔ آزاد.
{{Category|somecat}} => [[Category:somecat|{{PAGENAME}}]]
This template is for cases where the default category sort key {{FULLPAGENAME}} makes less sense than {{PAGENAME}}, it's merely a shorthand. There's no default for the parameter somecat to catch errors.
Note the pipe symbol in {{Category|somecat}} - with a colon what you'd get is certainly not
.