Bruce Wayne was the son of Thomas and martha Wayne, he had a happy life until he was 8 years old when while walking through an ally with his parents they were shot and killed by a small time criminal named Joe Chill, from that moment Bruce swore he would rid the city of evil, he knew he would need intense physical and mental training

Why Batman ?. Bruce Wayne had a phobia of bats, when he became a crime fighter he decided to use his fear as a symbol that would strike fear into criminals so he became The Bataman