Openness, whether the software is open source or proprietary
Repository model, how working and shared source code is handled
Shared, all developers use the same file system
Client–server, users access a master repository server via a client; typically, a client machine holds only a working copy of a project tree; changes in one working copy are committed to the master repository before becoming available to other users
Distributed, repositories act as peers; typically each user has a local repository clone with complete version history in addition to their working files
Active
AccuRev [proprietary, client-server] [proprietary, client-server] – source configuration management tool with integrated issue tracking based on "Streams" that manages parallel and global development; replication server is also available; now owned by Micro Focus
Autodesk Vault [proprietary, client-server] – Version control tool specifically designed for Autodesk applications managing the complex relationships between design files such as AutoCAD and Autodesk Inventor
CVSNT – cross-platform port of CVS that allows case insensitive file names among other changes
OpenCVS – unreleased CVS clone under a BSD license, emphasizing security and source code correctness
Darcs [open, distributed] – originally developed by David Roundy; track inter-patch dependencies and automatically rearrange and cherry-pick them using a theory of patches
Fossil [open, distributed] – written by D. Richard Hipp for SQLite; distributed revision control, wiki, bug-tracking, and forum (all-in-one solution) with console and web interfaces; single portable executable and single repository file
Git [open, distributed] – designed by Linus Torvalds for Linux kernel development; decentralized; goals: fast, flexible, and robust [1]
Global Design Platform (GDP) – [proprietary, client-server] design data management for IC design and Perforce infrastructure support
Helix Core (formerly Perforce Helix) [proprietary, client-server] – for large scale development environments
Mercurial [open, distributed] – written in Python as an open source replacement to BitKeeper; decentralized and aims to be fast, lightweight, portable, and easy to use
Panvalet [proprietary, shared] – Around since the 1970s, source and object control for IBM mainframe computers
Revision Control System (RCS) [open, shared] – stores the latest version and backward deltas for the fastest access to the trunk tip[4][5] compared to SCCS and an improved user interface,[6] at the cost of slow branch tip access and missing support for included/excluded deltas
Source Code Control System (SCCS) [open, shared] – part of UNIX; based on interleaved deltas, can construct versions as arbitrary sets of revisions; extracting an arbitrary version takes essentially the same time and is thus more useful in environments that rely heavily on branching and merging with multiple "current" and identical versions
StarTeam [proprietary, client-server] – coordinates and manages software delivery process by Micro Focus, formerly Borland; centralized control of digital assets and activities
Subversion (SVN) [open, client-server] – versioning control system inspired by CVS[7]
Vault [proprietary, client-server] – version control tool by SourceGear; first installation can be used for free
Obsolete
The following have been discontinued or not released in more than a decade.
Bazaar – [open, distributed] written in Python, originally by Martin Pool and sponsored by Canonical; decentralised: goals: fast and easy to use; can losslessly import Arch archives; replaced by friendly fork named Breezy
BitKeeper [open, distributed] – (discontinued) was used in Linux kernel development (2002 – April 2005) until its license was revoked for breach of contract; open-sourced in 2016
Code Co-op [open, proprietary] – (discontinued) peer-to-peer version control system (can use e-mail for synchronization)
^Bill Wohler (10 Oct 1992). "Unix – Frequently Asked Questions (7/7)". RCS vs SCCS: How do they compare for performance?. [RCS ...] is much faster in retrieving the latest version
Years, where available, indicate the date of first stable release. Systems with names in italics are no longer maintained or have planned end-of-life dates.