Travis Bickle
Travis Bickle is the protagonist of Taxi Driver, and it is through his eyes that we witness all of the events of the film. Indeed, the camera often takes Travis's subjective point of view, and we view what he is looking at through the windshield or window of his cab. His perspective is informed by his deep loneliness, alienation, paranoia and an existential disconnect from other people. He dreams of "cleaning up" the streets of New York and effecting change in his environment, but remains mainly frustrated, until he commits the final shocking act of violence at the brothel.
Travis Bickle is often lumped in with other post-traumatic Vietnam vets who populated so many movies in the 1970s and 1980s, but Robert De Niro's portrayal and Martin Scorsese's expert direction ensure that Travis is a three-dimensional (if deeply flawed) exception to the trope. While Travis is an ignorant bigot, an attempted assassin with a vitriolic distaste for minorities and all things countercultural, Travis's ultimate violent act is in the service of the safety of a child prostitute. His heroism is depicted both sensitively and ambivalently, flaws and all, which makes Travis such a memorable and iconic protagonist of 70s cinema.
Betsy
Betsy is a wholesome and beautiful campaign worker for Presidential candidate Charles Palantine. She exists as a complete fantasy for Travis's romantic imagination. Travis puts Betsy on a pedestal, never really seeing or understanding the real Betsy. Instead he projects all of his fantasies of innocence onto her. Her blonde hair and the white dress she is wearing when Travis first encounters her symbolize her innocence in Travis's starkly moralistic, conservative, and paternalistic mind.
The viewer sees Betsy through Travis's perspective throughout much of the film, which leaves her seeming cold, shallow, and somewhat one dimensional. However, it is important to keep in mind the film's skewed perspective through Travis's eyes. When we see Betsy interacting with her co-worker Tom in the office, we see Betsy as playful, intelligent, ambitious, and good-humored. While Travis may interpret Betsy as an innocent damsel in need of protection and rescue, she fails to live up to his fantasy, and he knocks her completely off her pedestal, to disastrous and violent effect.
Iris
Once Betsy disappoints Travis and proves to be just as cold as the world he wanted to "save" her from—at least in his eyes—Travis turns his knightly intentions to Iris, a precocious, rebellious, and lost 12-year-old prostitute. After a few brief encounters with Iris while driving his cab, Travis meets her through her pimp, but refuses to engage in sex with her.
Iris is scrappy, good humored, and impressionable, at turns easily influenced by her manipulative pimp, and startlingly tough and wise for a 12 year old. Iris has run away from suburban Pittsburgh chasing the counterculture of New York City, and is drawn into the orbit of the dangerous Sport. She is obsessed with astrology, referencing it several times over breakfast, and she confides in Travis about her dream of commune living in Vermont. She laughingly perceives Travis as "square" and asks him if he is a "narc."
Matthew, or "Sport"
Sport is Iris's pimp and the antagonist of Travis's hero's journey. Travis views him as a repulsive figure (which, to be fair, he is), a pimp of young girls, who treats women like objects and disrespects them for profit. Sport wears his hair long and considers himself "down" with hip culture, in contrast with Travis's "square" demeanor. In fact, Sport mistakes Travis for a cop upon first meeting him.
Sport sees Iris not only as one of his prostitutes, but as his "woman," a kind of girlfriend. As sleazy and horribly unethical as Sport is, his relationship with Iris is surprisingly emotionally and psychologically intricate, tender and feeling. While Sport is hardly painted as a sympathetic figure, his moral ambiguity serves as a foil to Travis's black-and-white moral code.
Tom
Tom works alongside Betsy in the Palantine campaign headquarters and is situated as a foil to Travis. Like Travis, he is in love with Betsy, although he knows the real Betsy in a way Travis can never hope to. Where Travis is blunt and unformed, Tom is self-aware, witty, and urbane. Because he represents everything that Travis is not, he becomes the perfect target for Travis's resentment.
Wizard
Wizard is an older taxi driver who dispenses advice and anecdotes freely at the diner where the taxi drivers convene. If there was ever any doubt as to whether Travis sees himself as a knight in search of a dragon to slay, the introduction of a character named "Wizard" should confirm the mythic proportions of his quest. Travis seeks the counsel of Wizard following Betsy's rejection of him, but Wizard's philosophical meandering and ultimate urging to get laid or get drunk, to roll with the punches, leaves Travis cold. Wizard is one of the few jolly characters in this otherwise joy-less story.
Charles Palantine
A few years after Taxi Driver was released, a man named John Hinckley attempted to assassinate Pres. Ronald Reagan. Subsequent details revealed that the motivation behind the shooting was a desire to impress actress Jodie Foster, the teenager who had played Iris.
Palantine is the senator running for president for whom Betsy and Tom work. Palantine’s political platform urges citizens to rise up and claim their power. Ironically enough, his "power to the people" rhetoric speaks directly to Travis's desire to enact change, however misinterpreted the message may be. Travis obsesses over Palantine following Betsy's rejection, and even attempts to assassinate Palantine, before being apprehended by the Secret Service.
Concessions Girl
A concessions salesperson at the porn theater who turns Travis down.
The Hall Monitor
The man who rents the room to Iris and Travis in the brothel, whom Travis eventually kills.
Personnel Officer
The man at the taxi depot who interviews Travis for the job.
