The Catholic Difference at Christmas

Since I've become aware of the liturgical calendar, my Christmas experience has been greatly enriched. This is fresh on my mind as yesterday was the last day of the Christmas holiday. Before I was exposed to Catholic thought, I had no idea what advent was about. I remember when I was about 4 years old, I had a calendar that when you opened the different days leading up to Christmas, you got a piece of chocolate from inside the calendar. No one really explained to me that it was a penitential season