layout is represented by a grid of spaces that are either empty or solid and form a flat plane containing walls of equal height. The game contains a default maze layout, but players can provide their own upon starting the game. The player can move forward and backwards between spaces at a rate of one space per key press and can turn left or right or look behind themselves in 90-degree increments. They can also peek around corners, which changes their view as if they had both moved forward and turned, but does not move their player character or allow them to shoot. Other players in the maze are displayed as the letters of their usernames along with an indicator of which direction they are looking; later versions of the game replaced this with the image of an eyeball. Players can also send text messages that are displayed on the screens of other players. Players can shoot bullets, which rapidly move away from the player and hit other players upon touching them; shooting a player earns the shooter ten points, while being shot loses the target five points. After being shot, the target has two seconds to move away before they can be shot again. The players' scores are displayed next to the view of the maze. Early versions of the game let the player overlay the screen with a top-down view of the maze and their avatar's position in it, while later versions kept the top-down view next to or below the viewscreen at all times. Different versions of the game support different numbers of players; the initial concept only supported two players, while the first main version of the game supported eight players at different terminals, and later variants supported more. In addition to human players, "robot" players can be added to the game, which follow simple algorithms to play the game and slow down if they reach a score limit. Development Maze The original version of the game was developed by high school students Steve Colley, Howard Palmer, and Greg Thompson in mid to late 1973 during a school work/study program at the NASA Ames Research Center in Silicon Valley, California. The trio were working on creating graphical representations of computational fluid dynamics on Imlac PDS-1 minicomputers, which unlike many other minicomputers at the time included a vector graphics monitor. Colley was developing a method of determining