"Each Star Trek series' cast includes a main character who seeks to understand human emotion: Spock the Vulcan-human hybrid (Star Trek, known to fans as The Original Series - TOS); Data the android (Star Trek: The Next Generation - TNG); Odo the shapeshifter (Star Trek: Deep Space Nine - DS9); Tuvok the Vulcan and the Voyager's holographic Doctor (Star Trek: Voyager - VGR); and yet another Vulcan, T'Pol, a female for once (Star Trek: Enterprise - ENT). While the Vulcans suppress strong emotions beneath the veneer of logic, emotionless Data seeks to become more human and Odo, capable of mimicking human beings, dispassionately observes human nature with curiosity, rarely envy."