Wikipedia indexes are a type of general topics list of encyclopedic content available on Wikipedia (the other type being Wikipedia outlines). The most common form of list on Wikipedia are item lists. Item lists present the members of a particular class (e.g., List of dog breeds), and do not belong in this category. The scope of a general topical index is everything about a particular subject (e.g., Index of Germany-related articles).

Indexes are alphabetical lists, while outlines are hierarchically structured. Outlines go in Category:Wikipedia outlines.