The Unix billennium was reached on 9th September 20001 at 01:46:40 UTC. The day marks the beginning of the use of the 10-digit denial Unix time stamps. The Unix time, also known as POSIX time or Epoch time, started on Thursday, 1st January 1970 00:00:00 UTC. It does not count leap seconds and, thus, is not an accurate representation of time.