The hanukiah is a specific type of menorah used for Chanukah. Chanukah is the festival of lights that falls in December. It is the celebration of the miracle that a quantity of oil lasted for eight days when it should have only lasted for one. A hanukiah is made up of nine branches. Eight of the branches symbolise the lasting of oil for eight nights while the ninth branch is the shamash (the master light). The branches of a menorah may differ in number and in height. However, to be considered a hanukiah the eight branches must be of uniform height and spacing. During Chanukah Jewish families may place their hanukiahs in the window of their homes to remind people of the miracle of Chanukah.