Topic summary
Version control systems

Extracted from the Wikipedia article Version control.
Overview
Many version control systems identify the version of a file as a number or letter, called the version number, version, revision number, revision, or revision level. For example, the first version of a file might be version 1. When the file is changed the next version is 2. Each version is associated with a timestamp and the person making the change. Revisions can be compared, restored, and, with some types of files, merged.