The Key Concepts Behind Branching

There are two important lessons that you should remember from this section. First, Subversion has no internal concept of a branch—it knows only how to make copies. When you copy a directory, the resulting directory is only a “branch” because you attach that meaning to it. You may think of the directory differently, or treat it differently, but to Subversion it's just an ordinary directory that happens to carry some extra historical information.

Second, because of this copy mechanism, Subversion's branches exist as normal filesystem directories in the repository. This is different from other version control systems, where branches are typically defined by adding extra-dimensional “labels” to collections of files. The location of your branch directory doesn't matter to Subversion. Most teams follow a convention of putting all branches into a /branches directory, but you're free to invent any policy you wish.