Christmas is a proper noun, so it is typically capitalized when used as the name of the holiday. For example, "I love Christmas!" or "Christmas is my favorite holiday." However, when used as a common noun, such as "the Christmas season" or "a Christmas gift," it is not capitalized. It is important to note that Christmas is not the only holiday that is capitalized in this way. Other examples include "Easter," "Halloween," and "Thanksgiving."