I have had a lot of questions lately about making patches. On Backtrack we get a lot of user submissions and many times we need a patch rather than a modified source file. The reason being is that a patch can be documented and contains the specific changes made to the source file and can also be easily reverted. Patching is also crucial if you fix a bug in a program and would like to submit the fix to the author. In any case being able to create a patch is very useful if you are working with Linux or any sort of programing stuff.
I decided to make a short post on how to make a patch and apply it: