Kami

Kami (神様, Kami-Sama; lit. "god," "deity" or "divine being") is one of the beings that have served as a Guardian of the Earth. Throughout a majority of the story, the character known as Kami on Earth is a wise Namekian who no longer even remembers his real name. It was revealed, however, that his father's name was Katas. As a nameless Namekian, he hatched on Planet Namek in Age 242 and, as a child, was launched by Katas into outer space in a Namekian spaceship which requires at least a basic knowledge of the Namekian language to pilot. Kami is also the Namekian that created King Piccolo and Earth's version of the Dragon Balls.
It is not known what Kami's personality was like originally, but after purging himself of his evil counterpart he becomes a normal peaceful Namekian for the most part. Though he could count as a Warrior-type Namekian, he gives up martial arts almost completely after becoming Guardian of Earth (though, he later fights Piccolo Jr. as Hero and Garlic Jr. as himself). According to Korin, Kami does not like visitors and will send any rocket ship trying to reach him back (implying it has happened at least once). His need for seclusion may stem from growing up by himself in the remote Yunzabit Heights. Despite having a legitimate care for the Earth, he began to think all humans were selfish and distrustful as he watched humanity grow and rebuild after the King Piccolo wars, until he meets Goku, which renews his faith in humanity (despite Kami knowing Goku is not from Earth, though it may have been Goku's love for his friends that changed Kami's mind).
At some point in his adult life, he arrived at Kami's Lookout, the home of the guardian of Earth at the time and became his apprentice in hopes the aging guardian would choose him to be his successor when he died. Although loyal to the aging guardian and even successfully outclassing the Makyan Garlic who competed with him, he was ultimately denied by the old guardian because of his selfish desire to become guardian due to its benefits, and because of the evil that dwelled within, although the Nameless Namek was a majority good.
He finally became Kami after separating the evil from of himself in order to attain the position, forming an evil twin brother calling himself King Piccolo who shared a lifeline with him (if one died, the other would also). He watched over the Earth from his lookout during King Piccolo and his mutated sons' initial rampage but eventually in a series of long, complicated circumstances they were defeated by the forces of Master Mutaito. He later created the Dragon Balls to give the people of Earth hope and encourage acts of bravery after King Piccolo's reign, though he later regretted it until he met the pure-hearted Goku.

Information from:
http://dragonball.wikia.com/