This option allows the patch program to compensate for any changes in whitespace (such as minor indentation changes) that would ordinarily cause some hunks of the patch to fail.

These actions include things like depressing a key (NoteOn), releasing a key (NoteOff), changing a synthesizer program or patch setting and movement of a pitch wheel to alter a note's pitch.

UML is a kernel patch that allows the Linux kernel to be compiled into a binary that you can run as a normal program.