In the Terminator franchise, a Terminator is an autonomous cyborg, typically humanoid, conceived as a virtually indestructible soldier, infiltrator, and assassin. A variety of models appear throughout the franchise. Within the fictional storyline, Terminators are created in a post-apocalyptic future by a computer AI known as Skynet, after it has launched war on humans. The machines are created to aid Skynet in its quest, and most are designed as infiltrators with a human appearance. Several Terminators throughout the franchise are reprogrammed by the human resistance to instead serve as protectors.

Skynet is an artificial neural network-based conscious group mind and artificial general superintelligence system that serves as the antagonistic force of the Terminator franchise.