DJ Hero is a rhythm video game and a spin-off of the Guitar Hero series. The game was developed by FreeStyleGames and published by Activision worldwide in October 2009 for the PlayStation 2 and 3, Wii, and Xbox 360 consoles. The game is based on turntablism, requiring the use of a special game controller that includes a turntable surface with three buttons, a crossfader bar, and an effects dial, in addition to other controller buttons used to manipulate in-game menus. In a manner similar to Guitar Hero, players use the turntable controller to mimic the actions of a disc jockey (DJ), such as scratching and crossfading between two different songs, as graphical representations of these actions scroll down on screen towards the player in time with the music. Unlike previous Guitar Hero games, there is no performance meter, and instead players are simply challenged to obtain the best score possible in order to earn stars (from zero to five for each mix) to unlock new songs, venues, and characters. The player can attempt these songs at one of five difficulties (Easy to Expert), with higher difficulties providing more actions for the player to perform within the song.