[Angelousss]

i assume you mean the bebop crew.
Jet is an ex cop(the black dog, cause when he bites a crook he doesn't let go) he was set up and lost his arm. He decided to become a bounty hunter.
Spike used to be in a crime syndicate and escaped. He and Jet became partners on jet's ship the bebop.
Ein is a dog who's been genetically altered to make him smarter.
Faye was cyrogenically frozen and can't remember any of her past before she was frozen. She offically joins the crew after having a couple of run ins with the crew.
Ed(one of my favorite anime characters period) is an eccentric child prodigy of a hacker, known in the hacking community as Radical edward. she's kind of an orphan.