John D. Harris is a well-known computer programmer, hacker, and author of some classical 1980s Atari computer games.
A lot of work carried out early in John's career is considered as groundbreaking in the industry. This is a fact which is interesting, because unlike other developers who were writing new games, based on new ideas, John's work mostly consisted of taking games which already existed and rebuilding them for a machine he had become obsessed with, the Atari 800.
His love for this particular machine eventually led him to creating some of the greatest games which were made available to the public, perhaps most of all, Frogger, which by the end of development had been written from scratch, twice. The reason for this is that his entire back catalogue of development tools and libraries he had developed were stolen at a game developer conference at which he was presenting. This actually pushed John into a period of depression, with which modern hackers / developers are unable to relate. The delay in writing the game also led to complications between Harris and his employer, Ken Williams (Director of Sierra On-Line).
During John's time at Sierra, he became one of the most influential young developers in America, at 24 years of age he was earning a 6 figure income off the back of royalties for games which Sierra were marketing for him. As time went on John's increasingly worrying relationship with Sierra began to get worse, the cutting of royalties and the lack of recognition for his work soon became a catalyst which led to him leaving the company to work at Synapse (despite many offers of employment from new startup EA games).