CategoryCategory is the root category and contains a list of categories. The categories are mostly usefull for their BackLink value.

See also:

FixMe: A general description about how to categorize the smart way, would be nice.

I hope this is a good place to write this. I found a lot fo cunfusion about persona user page: see ?PersonalPage, ?WikiHomepage, ?CategoryDebianWikiUser, CategoryHomepage --PaoloPan