This year, Hanukkah and Christmas overlap. The Jewish holiday, which celebrates the miracle of the oil that lasted eight whole days, begins on December 24 at sundown, just as Santa's sleigh takes off to deliver presents to every child in the world overnight.If you're a fan of The OC, you probably already know this and have spent the past three weeks gluing fake white fur to your yamaclaus . If you're not, well, allow me to introduce you to a brilliant holiday known as Chrismukkah.Obviously, people have been celebrating both Christmas and Hanukkah combined since long before The OC came along. But the actual term — or portmanteau, if you want to get fancy about it — "Chrismukkah" was first used by Seth Cohen to describe the uber holiday he invented to reconcile his interfaith upbringing.OC creator Josh Schwartz has said that the idea stems out of his own experience as an East Coast Jewish kid moving to California for college."I felt very much like an outsider," he explained to Vulture in 2013. "Even trying to talk about Hanukkah with some of them was like coming from an alien planet and talking about life there. The show is really about outsiders: Ryan was the most obvious outsider, as was Seth. The idea of a mixed [half-Jewish, half-Christian] family in Newport would also contribute to the Cohen outsider-family status. That part of their identity was always very important. Seth coined a holiday that would both celebrate and underline his outsider status in Newport. That led us to Chrismukkah."Fun fact: It was almost called Hanimas. (Let's let that sink in for a minute.)So, what exactly goes into a Chrismukkah celebration? Grab some eggnog and spin a dreidel as we walk you through the essential elements.