The Year 2000 problem (also known as the Y2K problem, the millennium bug or the Y2K Bug) was the result of a practice in early computer program design that caused some date-related processing to operate incorrectly for dates and times on and after January 1, 2000. It caused widespread concern that critical industries (such as electricity or finance) and government functions would cease operating at the stroke of midnight between December 311999 and January 1, 2000 and on other critical dates which were billed "event horizons". This fear was fueled by the attendant press coverage and other media speculation, as well as corporate and government reports. People recognized that long-working systems could break down when the 97, 98, 99 ascending numbering assumption suddenly became invalid. Companies and organizations world-wide checked and upgraded their computer systems. While no significant computer failures o