The meaning of Advent

We often hear of the "meaning of Christmas." What about the period leading up to it, though, Advent? What is its meaning?

As we prepare for Christmas, it is important that we find time for self-contemplation and carry out an honest assessement of our lives. May we be enlightened by a ray of the light that comes from Bethlehem, the ligh of He who is "the Greatest" and Himself small, He Who is "the Strongest" but became weak. ~ Benedict XVI, Angelus address, Sunday, December 4, 2011