Barney is a two hundred million year (two dinosaur years) old, six-foot tall, purple tyrannosaurus rex with a green tummy, who comes to life through a child's imagination. He is best known for his friendly, kind, optimistic personality and positive attitude.
Baby Bop is a minor character in the Backyard Gang video series and a main character in the Barney & Friends television show. She is a bright green triceratops, and also one of Barney's best friends. She made her debut in Barney in Concert (1991) and she has been on the show ever since then. Her name has been given by the Backyard Gang. Originally two years old, Baby Bop turned three years old in the episode "Look at Me, I'm 3!".
BJ is a 7-year-old yellow male Protoceratops who has been on the show since Season 2 (1993). He is the older brother of Baby Bop, whom he frequently calls "Sissy", though on rare occasions, he does call her by name. His theme song is none other than "BJ's Song". He wears a red baseball cap on his head and red sneakers on his feet. He has lost his favorite hat in the Season 3 episode "Hats Off to B.J.!". Sometimes, he says stuff to hide fears. For example, in "Barney's Halloween Party", he was shocked by the paper spiders. After learning they were fake, he replied "I knew that, sort of." Pickles are his favorite food and because of that, he actually has had them in different ways like pickles (also with pepperoni, peppers, pineapple and peanut butter) on a pizza (as seen in "Barney's Adventure Bus") or in mac-and-cheese (as mentioned in "E-I-E-I-O"). He also has a superhero persona, known as Captain Pickles. BJ also likes to run, jump, and ride around on his red scooter. Although he loves baseball, basketball and soccer, it's safe to say that BJ has never met a sport he didn't like. He still enjoys playing with his friends and helping his sister Baby Bop.
Riff is a six-year-old orange Hadrosaur who is B.J. and Baby Bop's cousin. One of his big interests is music and he is known for being able to imitate sounds really well. When he is excited, his stripes on his crest light up and blink quickly. He loves marching band and parade music as much as Barney does. Riff also likes to invent things, as shown in the video Let's Go to the Firehouse.