One of the best-known examples of data differencing is the diff utility, which produces line-by-line differences of text files (and in some implementations, binary files, thus being a general-purpose differencing tool). Differencing of general binary files goes under the rubric of delta encoding, with a widely used example being the algorithm used in rsync. A standardized generic differencing format is VCDIFF, implemented in such utilities as Xdelta version 3.