Specifications and history
As an example of the most advanced technology that Starfleet had to offer, this computer system was built into the vessel during the 2250s. Maintenance of the computer was under the supervision of Science Officer Spock from the ship commissioning in the year 2258.
In 2259, it was revealed that Admiral Alexander Marcus had included secret programming into the Enterprise computer. Robert April used a secret command to tranfer command and control of the ship away from the crew under one of Marcus's protocols. (TOS - Countdown to Darkness comics: "Number Three", "Number Four")