Tennis for Two, the World's First Graphical Videogame

Tennis for Two, the World's First Graphical Videogame: "Designing the circuit board and its components took Higinbotham a few days, and building the machine took about three weeks. On October 18th, 1958, hundreds lined up to play the newly christened Tennis for Two. It used a whopping five-inch oscilloscope screen, and featured play mechanics pretty similar to 1972's Pong, though the game was viewed from the side of the net rather than an overhead vantage point."