Christmas (Old English: Crīstesmæsse, meaning "Christ's Mass") is an annual commemoration of the birth of Jesus Christ[6][7] and a widely observed cultural holiday, celebrated generally on December 25[3][4][5] by millions of people around the world.[2][8] A feast central to the Christian liturgical year, it closes the Advent season and initiates the twelve days of Christmastide, which ends after the twelfth night.[9] Christmas is a civil holiday in many of the world's nations,[10][11][12] is celebrated by an increasing number of non-Christians,[1][13][14] and is an integral part of the Christmas and holiday season. --- While the birth year of Jesus is estimated among modern historians to have been between 7 and 2 BC, the exact month and day of his birth are unknown.[15][16] His birth is mentioned in two of the four canonical gospels. By the early-to-mid 4th century, the Western Christian Church had placed Christmas on December 25,[17] a date later adopted in the East,[18][19] although some churches celebrate on the December 25 of the older Julian calendar, which corresponds to January in the modern-day Gregorian calendar. The date of Christmas may have initially been chosen to correspond with the day exactly nine months after early Christians believed Jesus to have been conceived,[20] or with one or more ancient polytheistic festivals that occurred near southern solstice (i.e., the Roman winter solstice); a further solar connection has been suggested because of a biblical verse[a] identifying Jesus as the "Sun of righteousness". -- More, Christmas - Wikipedia, at: http://en.wikipedia.org/wiki/Christmas