History of WeBWorK version control
From July 2001 until June 2010, the WeBWorK project used the CVS version control system to manage the development of WeBWorK and provide up to date access to patches and bug-fixes.
In 2009, the MAA agreed to begin hosting WeBWorK courses for schools without their own WeBWorK servers and also to host the WeBWorK documentation and other aspects of WeBWorK's online presence. As a result, the WeBWorK codebase and NPL repository were transferred to an MAA server in June 2010, and at that time the switch was made from CVS to SVN.
Beginning in 2011 the WeBWorK project code base has moved to http://github.com/openwebwork. Starting with version 2.6 WeBWorK features a new collection of configuration files which vastly simplifies the upgrade process. (These were largely completed at the WeBWorK::Rochester code camp.). In general one should download the "master branch" of webwork2 and pg to obtain a super-stable version for production use. The current release candidate branch is usually fairly as well (it's release/2.7 as of this writing) and we encourage people to use it where appropriate to help us find the last remaining issues. The development version of WeBWorK and PG has the lastest features but is also the least well tested.
It is easy using git and github to download all three versions of the software and to switch quickly between the three versions. This allows you, for example, to work with the current release candidate but to quickly back out to the master branch if something goes wrong with the candidate release. See Github for instructions for downloading.