The result of technology during World War II using early CRT (Cathode Ray Tube) (Illustrated), based in American missile defence systems developed in the late 1940s, saw the fledgling birth of the video game industry. Some of these programs were adapted into other simple games during the 1950s. By the late 1950s, more computer video games were developed by defence contractor workers, while gradually increasing in their sophistication and complexity.

Gameplay
The player turns a control knob to position the CRT beam on the screen; to the player, the beam appears as a dot, which represents a reticule or scope. The player has a restricted amount of time in which to manoeuvre the dot so that it overlaps an aeroplane, and then to fire at the aeroplane by pressing a button. If the beam's gun falls within the predefined mechanical coordinates of a target when the user presses the button, then the CRT beam de-focuses, simulating an explosion.
In 1950 the Bouncing Ball video game program was developed for MIT's new Whirlwind Computer, the first computer to display "real-time" video signals, which was first demonstrated in April 1951 after being developed in the late 1940's. This was the very first computer capable of displaying both real time text and graphics on a video terminal, which at this time was a large oscilloscope screen. It was also the first computer to use core memory, which permanently stores binary data on magnets within a wire grid. While the Bouncing Ball game was not interactive, it was the precursor of video games to come in future years.

The rotary phone dial shown at centre of the picture was actually used to
make game moves.
In May, 1951, the NIMROD computer, created by the major UK electrical engineering and equipment firm Ferranti International was presented at the Festival of Britain. Using a panel of lights for its display, it was designed exclusively to play the game of NIM; this was the very first instance of a digital computer designed specifically to play a game in recorded history.
Gameplay
NIM is based on an ancient game dating back to at least the 16th Century,a two-player mathematical game of strategy, in which players take turns removing objects from distinct heaps. NIMROD could play either the traditional or "reverse" form of the game. On each turn, a player must remove at least one object, and may remove any number of objects provided they all come from the same heap. This is a simple game, where you start with a number of piles of tokens. Each player in turn takes one or more tokens from any one pile, and the game continues until the last token is taken from the last pile.


Gameplay
Players interacted with the "ball" using one of the two analog aluminium game controllers to click a button to hit the ball and use a knob to control the angle. Hitting the ball also emitted a sound. The controller device was designed in about two hours and was assembled within three weeks.
Excluding the oscilloscope assembly, all of the game's circuitry took up approximately the space of modern microwave oven.
