A branch tag is very much different from a normal tag. A normal tag can be just used to tag a particular version of sources and retrieve the exact version later. No independent development can happen based on a normal tag. However a branch tag creates a virtual branch in CVS repository sources and facilitates parallel development to happen on that branch. There is no limit on number of branches.

For example, if you plan to work on two releases of same project, you would want to create a branch for each release and work on them separately.

The creation of a branch is similar to creation of a normal tag but requires an extra option -b along with cvs tag command.

The following example shows how to create a branch in the CVS repository.

[neo@techpulp project1]# cvs tag -b release-branch-1
T src/main.c
T src/this.c
T makefile
[neo@techpulp project1]#

The following example shows how to check out code from the newly created branch.

[neo@techpulp ~]# cvs co -r release-branch-1 project1
U src/main.c
U src/this.c
U makefile
[neo@techpulp ~]#