What Does Revision Control System (RCS) Mean?

A revision control system (RCS) is an application capable of storing, logging, identifying, merging or identifying information related to the revision of software, application documentation, papers or forms. Most revision control systems store this information with the help of a differential utility for documents.

Techopedia Explains Revision Control System (RCS)

Most revision control systems run as independent standalone applications. There are two types of revision control systems: centralized and decentralized. Some applications like spreadsheets and word processors have built-in revision control mechanisms. Designers and developers at times use revision control for maintaining the documentation along with the configuration files for their developments. High-quality documentation and products are possible with the proper use of revision control systems.