DeltaRPM is a tool that generates RPMs that contains the difference between an old and a new version of an RPM. This makes it possible to recreate the new RPM from the deltarpm and the old one. You don’t have to have a copy of the old RPM, as it can also work with installed RPMs.The delta rpm packages are even smaller in size than the patch RPMs, which is an advantage when transferring update packages over the Internet. The drawback is that update operations with delta RPMs involved consume considerably more CPU cycles than plain or patch RPMs
