While a computer science student at Purdue University, Daniel Lawrence wrote several hobbyist computer games for the university's PDP-11 RSTS/E mainframe computer, and one grew into "Telengard". In his 1976 and 1977 college summer breaks at home, he worked at BOCES in Spencerport, New York, where he wrote a dungeon crawl game called "DND" (postdating the similar but unrelated "dnd") in the BASIC programming language for the DECsystem-10's TOPS-10 operating system. He had been influenced by the pen and paper role-playing game "Dungeons & Dragons". At college, he ported the game to Purdue's PDP-11 RSTS/E. The game's mechanics grew from conversations at the Purdue engineering building. Part of its real-time nature descended from the need to not have players monopolize the few shared computer terminals.