From the NannyMUD documentation

LAST CHANGE

2000-12-16

TOPIC

NAME
        rtfm - Read the f* manual.


DESCRIPTION
	This is the man page for 'rtfm', which means 'Read The F*
	Manual', where 'F*' is any appropriate word starting with
	'F'. Classically, the two words 'Fuck' and 'Fine' has been
	used.

	If you're reading this, you at least know how to use the 'man'
	command, which is a good thing.