In 1961, a new Digital Equipment Corporation PDP-1 mini-computer was installed at M.I.T. In order to demonstrate its full capabilities, including its cathode ray tube display, students Martin Graetz, Steve Russell and Wayne Wiitanen created a game which simulated a battle between two spaceships. They called it Spacewar! and it enabled two users to each control a spaceship using either the keyboard or a joystick.
It soon had a cult following and play at M.I.T. had to be banned during working hours. While it wasn’t the first-ever computer game, Spacewar! was the first shooter game and the first one to require quick reflexes. Today you can play Spacewar! using a browser-based PDP-1 emulator.