Goku was originally sent to earth to destroy it. His father Bardock never thought Kakarot would amount to anything so he dismissed the child. When Goku/Kakarot got to earth, the baby bumped his head on a rock and forgot all about his Saiyan ancestory and mission, and lived with and trained under "Grandpa" Gohan in the forest. Unfortunatly, because of his tail, Goku killed Gohan one night by transforming into Oozaru, or a giant ape with enormous power. After a series of goofy events, Goku meets Bumla, a crazy stubborn teenage girl searching for the dragonballs, and Yamcha, a road bandit. Both if whom wanted the Dragonballs so they could make their own wishes. However, when Goku refuses to give up the four star ball, or his Grandpa, he travels with them. Then Goku goes and trains under Master Roshi, or the Turtle Hermit, along with Krillin and enters a world martial arts tournament not to long after. He made it to the finals, but Jackie Chun, or Master Roshi in disguise, beats him after a long drawn out battle. Later along, Goku marries a woman named Chi Chi and has their first son named Gohan. Eventually, Goku is killed in the fight with Radditz, then wished back. A saga later, meets Vegeta, and arrogant Saiyan prince who loathes Goku, or Kakarot, as he insists calling him. Goku first reaches Super Saiyan level when he fights with Freeza, who had succeded in killing Krillin and Piccolo. Much later, he is killed again in an explosion he caused during the fight with Cell in an attempt to rid the earth of Cell. In between this time we find that during the fight with Cell, Chi Chi was pregnant with Goku's second son, Goten. He doesn't meet Goten until the tournament when he is allowed to return for one day. In the Buu saga, a Kai (I dunno which one, I believe the Supreme Kai) sacrafices his life so Goku can live and fight Buu. Up to this point, Goku can reach up to SSJ 3. In GT, Goku is turned to a kid again by Pilaf, anf then has to go in search of the Dark Star Dragonballs so that the earth is not destroyed. Later on in GT, Goku is able to reach SSJ 4 to fight Vegeta-Bebi. In the very final episode, Goku rides on the back of Shenlong, fuses with the dragonballs, and disappears (how sad! Tear!).
