No Chips
I intentionally consider the Odyssey as a video game and not as a computer game: unlike the consumer version of Atari's Pong, which followed a few years later, the Odyssey didn't contain any chip. The main part was formed by forty transistors and forty diodes, which made appear some movable spots and a stripe on the television screen. Those represented e.g. a ball and two paddles.

12 games
Still, the Odyssey was much more than a pong game. The box sold in the stores contained six 'cartridges' to play twelve different games. Of course one of the games was pong (simple called tennis by Magnavox). Other games were e.g. hockey, football, roulette and states, a game to help children learn the names of the states in the USA.

Overlays
To play a game the early game fanatic had to perform several actions. The right cartridge had to be chosen and plugged in the Odyssey (cartridges avant la lettre: the cartridges didn't contain any ROMs, they only acted like jumpers which closed the electrical circuit that was needed for a specific game). Besides, because the Odyssey couldn't generate any colours, the player had to use for every game another transparent, coloured plastic overlay, which could be attached on the television screen with some spittle. The overlays represented a tennis court or a roulette table, for example. For many games the player also needed extra accessories that were also present in the box, like a dice and playing cards. All together the Odyssey set contained besides the console about 300 objects. One had to remember or write down the score, which of course opened the door for cheating.

Ralph Baer
The genius behind all this and thus one of the pioneers of video gaming is Ralph Baer. Already in the early 50's he began thinking for the first time about using television for playing games.

Baer was born in 1922 in Germany. The Jewish family Baer emigrated in 1938 to the USA, where Ralph professionally started repairing television receivers. After his graduation on television engineering, he focused on designing television receivers. In 1951, he suggested one of his first employers to build games into TV sets. That got the predictable negative reaction, and the idea was frozen for many years.