Diff
Diff is a class of programming utilities that compares two or more files for changes or differences between them.
Diff as a file format
Although many newer diff tools have modified the output file format for more flexibility, the original diff output file format has become something of a standard since a number of utilities and systems can open up diff files for further processing or visualisation.
OS/2 text & programmers editors with diff file support
- Elvis - diff syntax support included by default - Open source - Current.
- FTE - Has support for syntax highlighting, code folding and syntax-aware autoindent.