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In computing, file comparison is the calculation and display of the differences and similarities between data objects, typically text files such as source code. The methods, implementations, and results are typically called a diff, after the Unix diff utility. The output may be presented in a graphical user interface or used as part of larger tasks in networks, file systems, or revision control. Some widely used file comparison programs are diff, cmp, FileMerge, WinMerge, Beyond Compare, and File Compare.