The word Christmas comes from the words Cristes maesse, or "Christ's Mass". Christmas is the celebration of the birth of Jesus for members of the Christian religion. Most historians peg the first celebration of Christmas to Rome in 336 AD. Christmas is both a holiday and a Holy Day. In America it is the biggest event of the year (especially for kids), and for members of the Christian religions it is an important day on the religious calendar. The federal government, all state governments, all schools/colleges/universities and the vast majority of businesses in America give employees one or two days off at Christmas, making it an important holiday (other federal holidays are: New Year's Day, Martin Luther King Day, Washington's Birthday, Memorial Day, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving). In the Roman Catholic calendar, Christmas is one of 6 holy feast days celebrated in America, the others being: Circumcision (New Year's Day), Ascension, Assumption (Mary's Assumption into heaven, August 15), All Saints (November 2), and the Immaculate Conception