The Terminator is a 1984 American science fiction action film directed by James Cameron, written by Cameron and Gale Anne Hurd and produced by Hurd. It stars Arnold Schwarzenegger as the Terminator, a cybernetic assassin sent back in time from 2029 to 1984 to assassinate Sarah Connor (Linda Hamilton), whose unborn son will one day save mankind from extinction by Skynet, a hostile artificial intelligence, in a post-apocalyptic future. Kyle Reese (Michael Biehn) is a soldier sent back in time to protect Sarah. The screenplay is credited to Cameron and Hurd, while co-writer William Wisher Jr. received an "additional dialogue" credit.

Cameron devised the premise of the film from a fever dream he experienced during the release of his first film, Piranha II: The Spawning (1982), in Rome and developed the concept in collaboration with Wisher. He sold the rights to the project to fellow New World Pictures alumna Hurd on the condition that she would produce the film only if he were to direct it; Hurd eventually secured a distribution deal with Orion Pictures, while executive producers John Daly and Derek Gibson of Hemdale Film Corporation were instrumental in setting up the film's financing and production. Originally approached by Orion for the role of Reese, Schwarzenegger agreed to play the title character after befriending Cameron. Filming, which took place mostly at night on location in Los Angeles, was delayed because of Schwarzenegger's commitments to Conan the Destroyer (1984), during which Cameron found time to work on the scripts for Rambo: First Blood Part II (1985) and Aliens (1986). The film's special effects, which included miniatures and stop-motion animation, were created by a team of artists led by Stan Winston and Gene Warren Jr.

Defying low pre-release expectations, The Terminator topped the United States box office for two weeks, eventually grossing $78.3 million against a modest $6.4 million budget. It is credited with launching Cameron's film career and solidifying Schwarzenegger's status as a leading man. The film's success led to a franchise consisting of several sequels, a television series, comic books, novels and video games. In 2008, The Terminator was selected by the Library of Congress for preservation in the United States National Film Registry.

An android assassin called a "Terminator" is sent back in time from 2029 to 1984 Los Angeles, programmed to hunt and assassinate a woman named Sarah Connor. Separately, a human soldier named Kyle Reese simultaneously arrives, intent on stopping the Terminator. After searching for addresses in a telephone directory, the Terminator systematically dispatches similarly named women, as well as several other people it comes in close contact with, including Sarah's roommate, Ginger, and her boyfriend, Matt. The Terminator eventually locates the correct Sarah at a local nightclub, where she is rescued by Reese during a mass shooting. The pair then steal a car to escape, with the Terminator pursuing them in a stolen police car.

As they hide in a parking lot, Reese explains to Sarah that an artificially intelligent defense network known as Skynet, created by Cyberdyne Systems, will soon become self-aware and trigger a global nuclear war to bring humankind to its extinction. Sarah's future son, John, will rally the survivors and lead a successful resistance movement against Skynet and its mechanical forces. On the verge of the resistance's victory, Skynet sent the Terminator back in time to assassinate Sarah, thereby preventing John's birth. Reese additionally divulges that the Terminator has a perfect voice-mimicking ability and a durable metal endoskeleton covered by living tissue to appear human.

The Terminator tracks Reese and Sarah, but it disappears after crashing during a car chase with the duo. The police apprehend Reese and Sarah. Sarah is notified of Ginger's and Matt's murder, while Reese is interrogated by Dr. Silberman, a skeptical criminal psychologist. The Terminator returns to a motel room it has been using as a base of operations to repair its damaged eye and right arm. It arrives at the police station searching for Sarah, slaughtering many officers in the process. Reese and Sarah escape, steal another car and take refuge in a motel, where they assemble several pipe bombs and plan their next move. Reese admits that he has adored Sarah since he saw her in a photograph that John gave him, and that he travelled through time out of love for her. Reciprocating his feelings, Sarah kisses him and they have sex.

The Terminator locates Sarah by intercepting a call intended for her mother. She and Reese escape the motel in a pickup truck while it pursues them on a motorcycle. In the ensuing chase, Reese is badly wounded by gunfire while throwing pipe bombs at the Terminator. Sarah knocks the Terminator off its motorcycle but loses control of the truck, which flips over. The Terminator, now bloodied and badly damaged, hijacks a tank truck and attempts to run down Sarah. Reese manages to insert a pipe bomb into the truck's hose tube, causing it to explode and reduce the Terminator to its endoskeleton. It pursues them into a Cyberdyne-owned factory, where Reese activates machinery to distract it, but it eventually discovers them. Reese then lodges his final pipe bomb into its midsection, blowing it apart, but at the cost of his own life. Its still-functional torso then pursues Sarah, but she manages to lure it into a hydraulic press that she uses to crush it, finally destroying the cyborg.

Months later, Sarah, now pregnant with John, travels through Mexico, recording audio tapes to pass on to him. At a gas station, a boy takes an instant film photograph of her, the exact one that John will one day give to Reese, and she purchases it. The gas station owner remarks that a storm is coming and she indicates her awareness, alluding to humanity's impending conflict against Skynet, before driving away towards it.