Patch files are most often created using the .patch file extension, although .diff is also common. Our recommendation is to use .patch as the file extension unless the project you are working on has a different naming convention. For the actual file name, it is best to use something descriptive without being too long. Spaces should be replaced with a dash (-) or an underscore (_) -- choose one and be consistent. It can also be helpful to include any applicable bug or ticket numbers should the patch fix something described in the project's bug tracking system. Look at the following example to get a better idea about how best to name a patch file.

Example: Fixing a bug that caused the date to be output in an incorrect format. This is bug #1517 in the project's bug tracking system.

Bad:   date.patch
Good:  format-date-output.patch
Best:  format-date-output-bug1517.patch