+ 1m--rsyncable0m
+ When you synchronize a compressed file between two computers,
+ this option allows rsync to transfer only files that were
+ changed in the archive instead of the entire archive. Normally,
+ after a change is made to any file in the archive, the compres-
+ sion algorithm can generate a new version of the archive that
+ does not match the previous version of the archive. In this
+ case, rsync transfers the entire new version of the archive to
+ the remote computer. With this option, rsync can transfer only
+ the changed files as well as a small amount of metadata that is
+ required to update the archive structure in the area that was
+ changed.
+