Galaxy Game is one of the earliest known coin-operated computer/video games. It was installed at the Tresidder Union at Stanford University in September, 1971, two months before the official release of Computer Space, the first mass-produced video game. Only one unit was built initially, although the game later included several consoles allowing users to play against each other.
An early 3D flight simulator game, released by Sega in 1970. It was an electro-mechanical arcade game, using video projection to display a 3D game world on screen. It features free-roaming, first-person flight shooting gameplay, making it the first primitive example of a flight simulator game, first-person shooter, and open world.