At its minimum, a form of cybernetic entertainment involving screen-based output interacted with through any manner of technologically mediated input--keyboard, joystick, gamepad, touchscreen, or sensor, that also maintains the ludological requirements of a game (to distinguish a video game from an online environment such as Second Life). Video games are sometimes also distinguished from computer games on the premise that a video game is comprised of a dedicated system.
Spacewar! is unanimously considered to be the first video game. It was designed by Steve Russell in 1962, to be played on the PDP-1 [Programmed Data Processor] (Herz 5).