Hanukkah (חנוכה, alt. Chanukah), also known as the Festival of Lights, is an eight-day Jewish holiday commemorating the rededication of the Second Temple in Jerusalem at the time of the Maccabean Revolt of the 2nd century BCE. Hanukkah is observed for eight nights, starting on the 25th day of Kislev according to the Hebrew calendar, and may occur from late November to late December on the Gregorian calendar.

The festival is observed by the kindling of the lights of a special candelabrum, the Menorah or Hanukiah, one light on each night of the holiday, progressing to eight on the final night. An extra light called a shamash, (Hebrew: "guard" or "servant") is also lit each night, and is given a distinct location, usually higher or lower than the others. The purpose of the extra light is to adhere to the prohibition, specified in the Talmud (Tracate Shabbat 21b-23a), against using the Hanukkah lights for anything other than publicizing and meditating on the Hanukkah story.

Hanukkah is mentioned in the deuterocanonical or apocrypha books of 1 Maccabees and 2 Maccabees. 1 Maccabees states: "For eight days they celebrated the rededication of the altar. Then Judah and his brothers and the entire congregation of Israel decreed that the days of the rededication...should be observed...every year...for eight days. (1 Mac.4:56-59)" According to 2 Maccabees, "the Jews celebrated joyfully for eight days as on the feast of Booths."