The year was 1973. They were high school seniors in a work-study program with NASA, tasked with testing the limits of the Imlac PDS-1 and PDS-4 minicomputers. Their maze program flickered into life with simple wireframe graphics and few of the trappings of modern games. You could walk around in first person, looking for a way out of the maze, and that’s about it. There were no objects or virtual people. Just a maze.

But Maze would evolve over the summer and the years that followed. Soon two people could occupy the maze together, connected over separate computers. Then they could shoot each other and even peek around corners. Before long, up to eight people could play in the same maze, blasting their friends across the ARPANET – a forebear to the internet. Two decades before id Software changed the game industry with Wolfenstein 3D and Doom, Colley, Palmer and MIT students Greg Thompson and Dave Lebling invented the first-person shooter.