Assertion: key's function | /r/HasProperty | pf
Facets:
Source sentences:
text: IBM use of function keys dates to the IBM 3270 line of terminals,[citation needed] specifically the IBM 3277 (1972) with 78-key typewriter keyboard or operator console keyboard version, which both featured 12 programmed function (PF) keys in a 3×4 matrix at the right of the keyboard.