The Quake II engine is a game engine developed by id Software for use in their 1997 first-person shooter Quake II. It is the successor to the Quake engine. Since its release, the Quake II engine has been licensed for use in several other games.

id Software LLC is an American video game developer based in Richardson, Texas. It was founded on February 1, 1991, by four members of the computer company Softdisk: programmers John Carmack and John Romero, game designer Tom Hall, and artist Adrian Carmack.