The holidays have occurred on the same day four times since 1900, according to Hebcal, a website that tracks Jewish holidays and the Hebrew calendar. Here's what you need to know about Christmukkah and this year's rare calendar quirk.

Hanukkah and Christmas fall on the same date this year. This year marks the fifth time over the last 114 years Hanukkah has started on the same day as Christmas. It won't happen again until 2035. Sometimes called Christmukkah,