In The Terminator, the time-traveling cyborg uses the model designation T-800.
The T-800 is an infiltration machine sent from the future to kill Sarah Connor before her son, John, can lead humanity’s resistance against Skynet. Its living tissue covering allows it to resemble a human, while its metal endoskeleton provides the strength and durability of a machine. Arnold Schwarzenegger plays the initial Terminator in the 1984 film.
The first movie presents the T-800 as a nearly unstoppable assassin. It does not tire, feel pain, or negotiate, and it methodically tracks Sarah through Los Angeles. The machine’s famous identification is often shortened in casual discussion, but “T-800” is the precise model designation used in the franchise.
The T-1000 belongs to Terminator 2: Judgment Day and is a different, liquid-metal design. The T-600 is an earlier, less advanced series mentioned in later franchise stories, while the T-X appears in Terminator 3. These distinctions make T-800 the specific answer for the original film.