This page defines a prefix.
Prefixes are used by this wiki to quickly alert the reader to the source of a statement. The most common of these is TV, which indicates the source is a televised story.
NOTVALID was formerly used on this Wiki as a prefix to denote any covered source, in any medium, which was not considered a valid source. It is currently being phased out, but you may still find it in archived discussions or earlier revisions of a given page.