Main Building Computers (MBC) where found in nearly all buildings of the 24th century, where they supervise and control all security and maintenance functions. Such computers had a limited number of logic circuits that allowed them to deal with natural abnormalities (tire, structural damage, cleaning, etc.) and unauthorized intruders (usually handled by calling on a security robot).
Each unit is tied to visual and audio monitors and most control 1-12 general household robots, 1-4 light engineering bots, 0-2 supervisory borgs and 1-4 security robots. Main building computers will obey people who show a particular Stage II I.D. that they are programmed to obey or who show a Stage IV I.D. Their robots will obey someone with the proper I.D., the main building computer or the supervisory borgs. Main building computers operate off both broadcast power and solar energy cells. Access to them is gained by showing I.D. at a computer terminal and typing commands into the terminal. Main building computers are seldom programmed to accept verbal orders.