December is the twelfth and last month of the year in the Gregorian Calendar, with 31 days. From the Latin decem for "ten" (it was originally the tenth month of the year, before January and February were inserted).
December begins on the same day of week as September every year.
In Ireland, December 26 is called St. Stephen's Day and is a public holiday. In the Irish Calendar the month is called Mí na Nollaig (literally "The Month of Christmas") and is the middle month of the Winter season.