The Christmas card.
We send these to our friends and family, and to people we don't often see, as a way of keeping in touch.
Some people put letters in them, giving news of what their family has been up to during the year.
Most people display them, they become part of the Christmas decorations.
During Advent, we remember the messages sent to people to announce the birth of Jesus.
From Gabriel telling Mary that she would bear the son of God, to the dream that warned the Magi not to go back to Herod, to the crowd of angels announcing Jesus' birth to the shepherds. They are all forms of Christmas greeting from heaven to earth.
The season of Advent is a time of anticipation of the celebration of the baby that would grow up to be our saviour.
It's important that we send each other greetings at this time of year, but let's not forget to greet Jesus as we celebrate his birth.