Linux Magazine: Downloading Source Trees 101

“If you’ve been using open source for a good length of time,
you’ve probably needed a feature or bug fix that’s only available
in the development tree of a open source project. For example, if
you want to use PostgreSQL with RTG, you have to download and build
the developers’ latest code…

“Unlike stable releases, which are usually conveniently
available for download as either source tarballs or binary
packages, development code is often only available from a project’s
source code repository. Typically, a repository is either a CVS
(http://www.nongnu.org/cvs/) or Subversion (SVN,
http://subversion.tigris.org/) repository…”