Master Control Terminals were an ingenious invention which entered widespread use in the First Tiberium War. While Nod and GDI were locked in mortal combat, both sides noticed that as the war was taking its toll, it became increasingly hard to staff bases with personnel, let alone maintain them. Facing these difficulties, technical R&D divisions of both sides started hasty development of a system that could not only monitor the status of a structure, but also run it entirely by itself. Shortly, a breakthrough was made.
The breakthrough came with the abandonment of an unwritten rule that technology exists to augment human abilities and adoption of a new one, that technology serves to eliminate need for human control and, by extension, human error.
The Master Control Systems were quickly developed and introduced. The system was not an AI, it was a highly sophisticated program, which monitored the structure's status and ran all of its processes, even those as complex as Tiberium processing. The system also utillize various sensor and robotic repair facility (and/or human technician) to diagnose, plan and repair the building in a effective matter. The system's heart was a highly advanced and miniaturized mainframe, embedded in a sturdy frame of a console, which also served as the control terminal for the system. The consoles were usually located in highly secure locations within the buildings and more often than not protected by sophisticated weapon systems. Due to their appearance, they soon became known as Master Control Terminals.
The system performed its role flawlessly, and soon field commanders did not have to worry about maintenance staff, as only a small crew was required to keep structures in operational shape, compared to large numbers required to work at once in the pre-MCS days.
The system had one main flaw - the console's sturdy frame, while resistant to indirect damage, was very weak when it came to explosives and fire - C4 demolition charges could make short work of the control system and render the facility in-operable, as a system once destroyed had to be replaced completely. Starting from the second tiberium war, EMP weapon also provide substantial damage. They can render the terminal, or the entire base, fall in blackout. The mechanism inside the control however have advanced so as it will automatically set on reboot if such situation materialized.