Unified diff
A unified [:Diff:diff] is a [:PatchFile:patch file] (or diff) in [http://www.gnu.org/software/diffutils/manual/html_node/Unified-Format.html unified format]. This is the most popular and prevalent form of diff file used today. Traditionally this was created by running diff with the "-u" option; however, Mercurial's diff command generates unified diffs for you.