A version number of snapYYMMDD is seeming not "right". It should simply be YYMMDD instead.
Version number of the server. By default it's a snapshot name with the current date. But this could be changed to a real version number if we ever did something unusual like made a proper release ;-)
This form allows you to request diffs between any two revisions of this file. For each of the two "sides" of the diff, select a symbolic revision name using the selection box, or choose 'Use Text Field' and enter a numeric revision.