In software development, the word commit is often used by Git in the same places other version control systems use the words "revision" or "version". It is a revision of a part of the software source code, staged using a source code versioning system as GIT, CVS or SVN.
A commit may comprise an individual change to a file, or changing and adding a whole set of files, and usually contains a commit message which is a brief description of what changes were made.
Commits allow keeping record of what changes were made to the source code, at what time, by whom, and for what reason.
Using a source code versioning system, a commit can be reviewed or reverted to at any time during the development process.