This is a maintenance category, used for maintenance of the Wikipedia project. It is not part of the encyclopedia and contains non-article pages, or groups articles by status rather than subject. Do not include this category in content categories.

This is a container category. Due to its scope, it should only contain subcategories.

This is a "holding category", no one should add themselves here directly, but instead pick (or create) a sub-category related to their most used/favourite instant messaging.