SyStem> (BOS) An early [when?] IBM {operating SyStem}. According to folklore, BOS waS the predeceSSor to TOS on the IBM 360 and it waSIPL' d from a card reader. It may have been intended for very Small 360' S with no diSkS and limited tape driveS. BOS died out really early [when?] aS diSkSSuch aS the 2311 and 2314 became common with the IBM 360, whereaS diSkS had been a real luxury on the IBM 7090. (1999-01-29)