Prime directive

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A prime directive was, according to the Fourth Doctor, "the first program that's laid into any robot's brain." (TV: The Robots of Death) It was usually their main function. It was usually programmed, or intended, that the machine couldn't deviate from its prime directive.

BOSS said that its directive was efficiency, productivity and profit for Global Chemicals. (TV: The Green Death)

K1's prime directive was to serve humanity and never harm it, which it unintentionally violated when it killed its creator. (TV: Robot)

The prime directive of the assassination program was to kill a single person, and thus could not harm others around them. (PROSE: The Murder Game)

Ander Poul stated that robots could not kill, as it was their prime directive. (TV: The Robots of Death)

Kamelion's prime directive was to obey the strongest will in the vicinity. (PROSE: The Crystal Bucephalus)

The prime directive of the robot trolleys at Megamart was to assist the customers. (PROSE: The Shopping Trolleys of Doom)

The term was once used in relation to living things. On Sunday, a swamp monster believed that life's prime directive was to reproduce, colonise and spread. (PROSE: Wetworld)