The Christmas novena, as it is now known, begins on December 16, nine days before Christmas, and ends on Christmas Eve. The novena is a lovely Advent tradition, originating in Turin, Italy in 1721 and continues to prepare hearts for the coming of Christ through the prophecies, psalms and Gospels.
From December 17 to 23, the liturgy uses seven short prayers that have special richness and importance. Known as the "O antiphons" or the "greater antiphons," these prayers compress and express the Old Testament Messianic hope for Christ. These antiphons are read each day at vespers and are used as the alleluia verse of the Advent Masses.
Visit this page for the complete novena: NOVENA