The shamash is the candle used to light the other candles of the Hanukkah menorah.
In Hebrew, shamash (pronounced shah-MAHSH) literally means “helper” (not to be confused with shemesh, which is spelled the same and means “sun”). Sometimes, the sexton — or the person who helps run synagogue services — is known as a shamash, though in that case it’s more commonly pronounced SHAH-miss. Likewise, the shamash helps in the lighting of the menorah.
On most menorahs, the shamash is distinguished in some fashion from the other candles, either by offsetting it to one side or raising its level above the others. But this should not be understood as a sign that the shamash is somehow more important than the others. On the contrary, it is the eight other candles, one for each night of the holiday, that constitute the core of the mitzvah.
The presence of a shamash is one feature that distinguishes the Hanukkah menorah — also known as a hanukkiah — from the menorah used in the ancient Temple, which had seven branches all of equal height.
After lighting the Hanukkah candles, the shamash has served its purpose, though it’s not customary to blow it out but to let it continue to burn along with the other candles.