Subversion

Subversion, otherwise known as SVN, is widely considered to be the fastest growing source control tool on the planet. This is due to several factors:

• The stand-alone SVN software is free
• It improves on many CVS short-comings
• It comes with a very active and supportive development community
• Support for this project can be purchase through CollabNet

The goal of the SVN project was to build a source control tool that fixed many CVS limitations.

To fully understand the history of SVN one also needs to understand CollabNet. This is taken directly from the CollabNet home page:

With 1.2 million users, CollabNet is the industry's most widely used collaborative platform for software development. The CollabNet platform supports globally distributed teams in a centralized, cost-effective way, yielding 20% to 30% annual savings through reduced development infrastructure costs, increased productivity, improved project visibility and shared access to software assets.

• Collab.net
• Subversion Tigris Org

History

From a CollabNet perspective, the SVN project started in 2000. After encountering numerous problems with integrating their flagship product CollabNet EnterPrise Edition with CVS, they decided to create a new open source tool that fixed the CVS limitations.

Hence, Subversion was born...

SVN Features

This means that if any part of the commit does not work, the entire commit will be ignored.

The concept is that it is an all-or-nothing commit process.

This ensures that you do not leave the code in an unstable state by having only part of a change committed.

Consistent Data Handling

By using a binary "diffing" algorithm, Subversion can use the same process for versioning binary and text files.

Directory Versioning

Directories are treated like the source files.

If you add, delete, or move the contents of the directory a new version of that directory is created.

You can track changes to the directory just like a file.

Efficient Branching and Tagging

SVN does not create a full copy of the project being branched or tagged.

It uses a server-side link when the branch or tag is created.

This ensures that branching and tagging are not a resource intensive operation.

Network Layer

By using WebDAV, it allows for access over http/https.

This usually means that there will be no issues when attempting access from behind a firewall and/or proxy.