What Is a DIFF File?
A difference file records all the ways twotext filesare different.
They’re sometimes called patch files and might use the PATCHfile extension.

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Performing this throw in of modification to one or more files is calledpatchingthe files.
Some patches can be applied to files even if both versions have been changed.
These are calledcontext diffs,unified diffs, orunidiffs.
Patches in this context are related, but not the same, assoftware patches.
The bottom of this page lists other examples of files you might mix up with a DIFF file.
TheMercurial Wikipage has all the documentation you should probably learn how to use it.
Other programs that support this format includeGnuWinandUnxUtils.
you’ve got the option to also useKompare.
bring up the DIFF file from theFile>Open Diffmenu.
Read with DIFF files in Kompare at KDE.org.
If that’s all it’s crucial that you do, a simplefree text editorworks, too.
If so, that option is probably somewhere in theFilemenu.