The invention was a tennis game simulated by a few resistors, capacitors, relays and transistors that reacted with the controller in order to make a ball bounce back and forth on the black and white screen, just like in a tennis game. The actual players couldn't be seen, actually they didn't exist at all, they were there theoretically but didn't show up on the screen. The only way the player became aware of his position was remembering the last impact with the ball, as far as I could realize. I may be wrong.
Even if the game was created in 1958, it was pretty good for its time, I must say. The ball was affected by gravity much like in real life, and to make it even more realistic, players had to carefully launch it over the net into the adversary's court. The perspective was a 2 dimensional one obviously, and player's were playing it watching from the side (not looking at the court from above).
The game was invented with the purpose to cure the boredom of visitors to Brookhaven National Laboratory, in which Mr. Higinbotham worked. The game was only brought out twice, on "Visitor's Day" at the power plant. Tennis for Two was the predecessor of PONG, one of the most widely recognized video games as well as one of the first
Just watch the video and "be amazed" at what 1958 technology was giving birth to: the world's first computer video game.
Content collected from : News SP
was that a game really 
