Air hockey is a game where 2 players play against each other on a low-friction table. Air hockey requires an air-hockey table, two player-held mallets, and a puck. A typical air hockey table consists of large smooth playing surface, a surrounding rail to prevent the puck and mallets from leaving the table, and slots in the rail at either end of the table that serve as goals. On the ends of the table behind and below the goals, there is usually a puck return. Additionally, tables will typically have some sort of machinery that produces a cushion of air on the play surface through tiny holes, with the purpose of reducing friction and increasing play speed.