Both Jewish and non-jewish families can commemorate this holiday, which celebrates a miracle that took place in one of the darkest hours in jewish history.
The word Hanukkah means "dedication" in Hebrew. And the miracle it dedicates occurred in 168 BC, when Syrian soldiers came to Jerusalem and desecrated the Jewish temple. For three years, the jews fought back, led by Judas Maccabaeus, one of the most famous heroes in Jewish history. Finally, the jews emerged victorious, and drove the Syrians from Palestine.
When they were ready to rededicate the temple, they discoverd, to their horror, that the perpetual lamp used for the purification rite had only the tiniest bit of oil...just enough to keep it burning for the day. Instead, the lamp burned for eight entire days, enough time to prepare more oil.
Hanukkah lasts for eight nights to honor this miracle. Each night another candle is lit on the manorah, a candelabra holding eight candles and the "shammash," the worker candle used to light all the others.
On the eighth night, a fully lighted menorah shines in the window a symbol of faith and hope for all to see.