Dende

Dende (デンデ) is a Namekian with an unique gift that allows him to heal others. Dende's first appearance was in Dragon Ball Z wherein Gohan and Krillin rescued him from Dodoria. On Goku's request, Dende became the Earth's Guardian in Kami's place. He continues his role as Guardian for the rest of the series, helping the protagonists during their adventures whenever he can.
Dende first appeared during the Namek Saga in Moori's village on Namek, which Frieza and his henchmen, Zarbon and Dodoria, were terrorizing in their search for the Dragon Balls. His brothers Moori and Cargo were killed, and Frieza's soldiers retrieved the village's Dragon Ball. Angered by Dodoria closing in on Dende, Gohan kicks Dodoria into a Namekian house, and with the help of Krillin, Gohan saves Dende, and they fly away from the village. After they sensed Vegeta killing Namekians in Tsuno's village, Dende, grateful for his rescue and confident in their good intentions, guided his saviors to the Grand Elder Guru. After the grand elder revealed Krillin's true potential, Krillin left Dende with Guru and brought Gohan for the Guru to reveal his true potential. Grand Elder Guru later revealed Dende's potential, allowing him to use his healing ability, and sends him to help Gohan and Krillin to summon the dragon Porunga because they couldn't speak the Namekian language to make their wish.
Dende eventually took part in the battle against Frieza. He mostly watched, but sometimes healed the fighters, and saved all of the their lives with his healing ability; such as Krillin after he got impaled by Frieza, Gohan after Frieza brutally pounded him, Piccolo after Frieza almost destroyed him with his crazy finger beams, and Vegeta who wanted to get a Zenkai to achieve Super Saiyan. With a lot of hesistance, due to the fact Vegeta had slaughtered a lot of Dende's own kind, Dende eventually heals Vegeta under Piccolo's orders. Though, he paid a serious cost when Frieza transformed into his final form and killed him with a single shot, in order to prevent him from healing anyone else. Later on, during Goku's battle against Frieza, Dende was revived from death by a wish made from Shenron and made the wish to Porunga to transport everyone except Goku and Frieza to Earth. When on Earth, Dende realized that Nail had fused with Piccolo. Dende lived on Earth for a while until it was time for the Namekians to be transported to New Namek.

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