GNU Savannah is a project of the Free Software Foundation initiated by Loïc Dachary, which serves as a collaborative software development management system for Free Software projects. Savannah currently offers CVS, GNU arch, Subversion, Git, Mercurial, Bazaar, mailing list, web hosting, file hosting, and bug tracking services. Savannah runs Savane, which is based on the same software as that used to run the popular SourceForge portal.
Savannah's website is split into two domain names: savannah.gnu.org for software that is officially part of the GNU Project, and savannah.nongnu.org for all other software.
Unlike SourceForge, Savannah's focus is for hosting free software projects and has very strict hosting policies, including a ban against the use of non-free formats (such as Macromedia Flash) to ensure that only free software is hosted. When registering a project, project submitters have to state which free software license the project uses.
In 2004, after a security compromise and resignations among the Savannah "hackers" (i.e. volunteers) team, FSF announced that it was going to move GNU Savannah from the Savannah (now Savane) software to GForge due to a mistaken perception that the codebase was now unmaintained. The Savannah hackers protested and the plan to migrate ceased.
Read more about GNU Savannah: Savane