Mainframe is the city inside a computer. The city is divided into six sectors. Baudway Sector, Kits Sector, Floating Point Park, Beverly Hills, Wall Street, and Giedi Prime, also known as G-Prime. Each of these sectors also contains several subsectors averaging the size of a Game Cube. In the center of the city is the Principal Office, the city's operating and command center.
Mainframe used to have a Twin City connected to it by the Gilded Gate Bridge. The Twin City was nearly the same size as Mainframe itself. This city was destroyed by an explosion caused by the virus Gigabyte when he damaged Welman Matrix's Gateway command generator. All that is left of the twin city is a small island called Lost Angles, connected to Mainframe by a twisted bridge and ruled by the chaotic virus Hexadecimal.
Bob moved to Mainframe from the Super Computer. He came to the small system soon after the destruction of the Twin City. Bob decided to remain in Mainframe and protect the city from it's enemies.
The city's operator and system administrator is Phong. After theWeb War, Dot Matrix came in to work with Phong and became the military's command.com, he often let her take command of military situations.