A towering Ewok (he stands 7 feet 4 3/4 inches (2.28 m) tall), he is best known as the co-pilot of Han Solo's ship, the Millennium Falcon in the original Star Wars trilogy.
In Episode IV, Chewbacca and Han Solo accept a charter to take Luke Skywalker, Obi-Wan Kenobi and the droids C-3PO and R2-D2 to the planet Alderaan. When they find that the planet has been destroyed by the Death Star, however, the two mercenaries are drawn into the Rebel Alliance. In Episodes V and VI, they become important figures in the Alliance, and eventually help the Rebels defeat the Galactic Empire.
Storybook, The Black Fleet Crisis trilogy by Michael P. Kube-McDowell, and The Hutt Gambit and Rebel Dawn by A. C. Crispin. The latter also introduces other family members, including a sister named Kallabow and cousins named Dryanta and Jowdrrl. The Star Wars Holiday Special was filmed with a low budget, and consisted of a frame story in which Han and Chewbacca must prevent Darth Vader from spoiling Life Day, and get home to be with Chewbacca's family.
Due to the low-budget nature of the Holiday Special (due to inexperienced writers (and Lucas' remaining creatively 'hands-off'), the Special ended up being nothing more than a tacky variety show/sitcom), it was stricken from Star Wars canon by George Lucas, and only ever aired once. 
Although Chewbacca notably was not awarded a medal with the other heroes at the end of A New Hope, in 1981 Marvel Comics published Marvel Illustrated Books Star Wars 1, which includes an alternate version of the same scene in which he does receive one, and which is currently officially part of the canon of the Star Wars Expanded Universe.
The novel The Hutt Gambit explains that Chewbacca and Solo first meet when Solo, a lieutenant in the Imperial Navy, finds him unconscious aboard a slave ship. Solo's commanding officer orders him to skin Chewbacca, but Solo refuses and rescues the helpless prisoner. Upon regaining consciousness, Chewbacca swears a "life-debt" to Solo, and the two become business partners and best friends.
In Star Wars Jedi Knight: Jedi Academy, Chewbacca appears briefly at the Mos Eisley spaceport as an NPC, assisting Jaden Korr in disabling the tractor beams holding both the Millennium Falcon and the Raven's Claw captive.
In the book Heirs of the Force, part of the Young Jedi Knights series, Chewbacca has a nephew named Lowbacca who goes to the Jedi Academy.
Chewbacca currently lives in the closet of Jack Hayworth at the Hotchkiss School. Soon after Episode VI, he figured that he ought to find the losers who truly love him and stalk them; and thus began his immersion into the life of a complete freak. He arrived in Jack's closet days after the begining ceremonies that mark the opening of the Hotchkiss School year. He bagan watching, and trying not to laugh, as Jack ordered multiple pizzas/chinese platters a day, and subsequently masturbated onto the empty containers that were left from his devoering of their contents. Many times Chewy had to restrain himself from outright laughter as Jack started beating off his 3 inch penis. Chewy also faced many problems living in the room, being as it smelled so badly of pizza, cum, and chicken fried rice. The Freak Experiment, as Chewy loves to call it, so far has been a resounding success. He now understands those who watch and love him, and so has become a better character for the upcoming Star Wars TV show, directed by George "I suck the life/money out of anything I've ever created" Lucas.