The "trunk" series represents the primary line of development rather than a stable release branch. This is sometimes also called MAIN or HEAD.
The latest stable release
This series includes the pre- and post-target hooks.
The Gant 1.7 series
The 1.6.x versions
The 1.5.x versions
The 1.4.x versions.
The 1.3.x version
The 1.1.x maintenance branch