It is possible, that a revision may also be a branch, a version and a release.
Those terms are sometimes used a little fuzzy, and my use may not be the definitive one. That said, in my nomenclature,
- a revision is a well definied snapshot of the project
- a branch is a named set of revisions, developed beside other branches. It is not uncommon to call the lastest revision of that set 'the branch' as well.
- a version is a revision that has been given a numerical name (i.e., the version number)
- a release is a version, that was given to the customers, or made public otherwise) (it may also refer to the process of releasing).