A menorah is a candelabra associated with Judaism.
Many menorahs have 7 candles: 1 taller one in the center and 3 to either side.
Menorahs with 9 candles are part of the celebration of Hanukkah. Sometimes they are referred to as a hanukiah חַנֻכִּיָּה. A hanukiah will have one special candle, a shammus or "helper" candle, and 8 other candles representing the 8 days and nights of Hanukkah. The shammus will be set off in some way, either higher or lower than the others or separated by physical space.