Christmas is a holiday that has been celebrated for thousands of years, and there are many theories about how it got its name. Some people believe that it comes from the Old English word "Cristesmæsse," which means "Christ's Mass" - the Mass is a service of the Christian church. Other people think that it comes from the Old English word "Crīstesdæg," which means "Christ's Day." Whatever the origin of the name, Christmas is a time of joy and celebration, and it's a wonderful time to spend with family and friends.