The 'Referer' attribute of an HTTP request is misspelled - should be 'referrer'

My favorite story of this kind comes from the early days at Apple Computer. Some highly skilled but illiterate programmers wrote a serial interface driver they called "The Inteligent Interface". Indeed it was.

The misspelling propagated itself into the driver's official published documentation with no one noticing. I guess inteligence [sic] is what inteligence [sic] does.