Repository
The directory storing the master copies of the files. The main or master repository is a tree of directories.
Module
A specific directory (or mini-tree of directories) in the main repository. Modules are defined in the CVS modules file. RCS
Revision Control System. A lower-level set of utilities on which CVS is layered.
Check out
To make a copy of a file from its repository that can be worked on or examined.
Revision
A numerical or alpha-numerical tag identifying the version of a file.