Revision
In Mercurial, the term revision can have two different meanings, depending on context.
Most often, "revision" refers to a distinct changeset in a repository, for example by specifying a repository-local revision number for the --rev option of the hg update or the hg merge command (conceptually referring to "a revision of the repository").
The term "revision" is also used as the short form for the longer term "file revision", which refers to a certain version of a file stored in the repository (conceptually referring to "a revision of a file").
This dual-use of the term "revision" naturally follows from the fact that Mercurial uses the same technical method for storing changeset information and for storing file versions in the repository, namely the revlog format (see Design).