What are facts about Goku from Dragonball

goku is the main character in the dragonball series and is a saiyan a human looking alien from planet vegeta vegetas dad planet.saiyans have a tail and have a lot of pride and are very mean and strong.goku was sent to earth to destroy it but a little while after that he hit his head on a rock by acsedent well he actually felled. then he forgot all about his plan to destroy.