The story of Hanukkah is that is was a very dark time in the life of the Hebrews. There was a tyrant on the throne, Antiochus Epiphanies, who treated them poorly. They were basically slaves, and he desecrated their temple. A leader by the name of Judas Maccabeus led a revolt called the Maccabean Revolt. They attempted to restore the temple again. The holiday of Hannukah celebrates the restoration of the temple as a place of hope during the dark time, and the miracle of the oil keeping the lamps lit for 8 nights, even though they only had enough oil for one night. That is why 8 candles are lit during Hannukah.