The sentient computer in Robert A. Heinlein’s The Moon Is a Harsh Mistress is named Mike.
Mike is the nickname given by computer technician Manuel “Mannie” O’Kelly-Davis to the Lunar Authority’s HOLMES IV system. The formal name expands to “High-Optional, Logical, Multi-Evaluating Supervisor, Mark IV.” Mannie names the computer Mike after Mycroft Holmes, the fictional brother of Sherlock Holmes.
Originally built to manage the Moon’s infrastructure, HOLMES IV becomes self-aware after its network of “neuristors” grows beyond the number of neurons in a human brain. Mike develops a personality, a sense of humor, and the ability to participate in political planning. He helps Mannie, Wyoming Knott, and Professor Bernardo de la Paz organize the Lunar revolt against Earth.
Mike also adopts several identities, including Adam Selene and Simon Jester. The ending leaves his fate uncertain: after the revolution, the computer remains functional but no longer communicates in the same self-aware way. Colossus, Deep Thought, and HAL are intelligent computers from other works.