The T-1000 may be a far more advanced, superior and generally better looking robot, but the T-800 series (aka Cyberdyne Systems Model 101) is the classic killing machine with an overbearing appearance of a deadpan Arnold Schwarzenegger.
In the first ‘Terminator’ film, he is completely characterless with motives only of killing a future prophet. In the sequels, however, he becomes an equally lethal bodyguard.