We recommend that you submit fonts in the OpenType format.
You probably do not need to worry about other formats at all, because OpenType encloses and extends both TrueType and PostScript Type 1, and it is currently the normal font format for GNU/Linux, Mac OS X and Windows.
See the foo-open-font-sources DVCS template for practical recommendations about the various formats and best practices on branch and tarball structure.
We highly recommend uploading a complete set of source files, such as the ".sfd" or ".vfb" files created by your font editor.
A "complete set" means all the files that you have used to create the final OpenType files.
By doing this, you immediately provide everyone with the material they need to enhance your font, or convert it to another format.
One size doesn’t fit all
There are lots of other font formats you can share here:
- PostScript Type 1
- X-Windows PCF