The A.D. (Latin, Anno Domini, In the Year of Our Lord) system was
     devised before "origin 0 counting" was invented, and the starting
     year was accordingly numbered 1.  So the 1st century was 1 to 100,
     the 2nd was 101 to 200, the 20th is 1901 to 2000...

     This is standard terminology no matter how much some of you may
     dislike it.  However, "a" century or millenium is any span of 100
     or 1000 years; so if you want to celebrate the end of "the
     century" or "the millenium", meaning 1900-1999 or 1000-1999, on
     December 31, 1999, you certainly can.  It just isn't the end of
     the "20th century A.D." or "2nd millennium A.D.".

     The starting year A.D. 1 was not, as stated previously in this document,
     the year in which Jesus was [incorrectly] assumed to have been born,
     but the following year, assumed to be the first full year of his life.
     The preceding year, 1 B.C., is when he was assumed to have been born.

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