Roronoa Zoro is a swordsman famous for his three swords style he uses in most of the episodes in one piece, I'm not one to know much, I really love one piece, but I've only started watching this month
Hes very cool and as a child made a promise to a girl called Kuina that one of them would be the greatest swordsman in the world. She died not long after.
He has looked death in the face a lot but when he found Hawkeye Mihawk he was left with an incredible wound but not killed as Hawkeye saw potential in Zoro and did not kill him.