Tardis:Prefixes

Prefixes are used to preface a story name, given as the source for a statement of fact in an article. In the example,
 * The Tenth Doctor once ate a part of a chocolate Easter egg. (TV: Planet of the Dead)

the prefix is TV.

Note that prefixes are a different and, in some ways, simpler system than dab terms (the parentheticals you find in page titles). Most prefixes cover several dab terms.

In-universe sources
Prefixes that are used on this site for the citation of stories are:

Invalid sources
Although invalid fiction can belong to various media, we find it easiest to use one catch-all prefix when citing invalid sources.

This helps make sure that no invalid sources are accidentally used by editors when writing an in-universe page in the main namespace: as their name implies, invalid sources can only be used as citations for in-universe pages that also bear the tag, or, alternatively, in the "Behind the scenes" section of a normal in-universe page.

Consequently, while some dab terms like "(stage play)" and "(feature)" will always be linked to the NOTVALID prefix, it is possible to see a comic story or even a TV story cited with NOTVALID.

Out-of-universe sources
Confined mostly to reference sources, the following prefixes may be used in any "real world" article, or in the "behind the scenes" section of an in-universe article. While the in-universe prefixes are strictly by medium, the out-of-universe ones emphasise type of material.

Commentaries
Commentaries are especially tricky, thanks in large measure to the Tenth Doctor's era, where some episodes have multiple commentaries. It's important to use the correct prefix, because, for example, PCOM: Doomsday is a wholly different thing to ICOM: Doomsday.

There is n associated dab term for commentary prefixes, because we do not give audio commentaries their own page; instead, we cover them in the "Behind the scenes" sections of the stories themselves.