+Delta Object
+~~~~~~~~~~~~
+
+The "delta" object is used internally by the object database to
+minimise storage usage by using xdeltas (byte level diffs). Deltas can
+form chains of arbitrary length as RCS does (although this is
+configureable at creation time). Most operations won't see or even be
+aware of delta objects as they are automatically 'applied' and appear
+as 'real' git objects In other words, if you write your own routines
+to look at the contents of the object database then you need to know
+about this - otherwise you don't. Actually, that's not quite true -
+one important area where deltas are likely to prove very valuable is
+in reducing bandwidth loads - so the more sophisticated network tools
+for git repositories will be aware of them too.
+
+Finally, git repositories can (and must) be deltafied in the
+background - the work to calculate the differences does not take place
+automatically at commit time.
+
+A delta can be created (or undeltafied) with
+link:git-mkdelta.html[git-mkdelta] it's raw data cannot be accessed at
+present.
+
+