Gohan, Goku and Chi-Chi's four-year-old son, was named after his adoptive grandfather. Physically, he resembles a young Goku, right down to his tail and his propensity to become a raging Giant Monkey when he looks at a full moon. Spiritually, he is good and pure of heart.
Because of his protective mother, Gohan begins life as something of a wimp, but when the Earth is threatened, he reveals his tremendous potential as a fighter. In one instance, he uncontrollably "powers up" in order to rescue his father from a desperate situation. Soon Gohan is forced into training in preparation for the eminent arrival of the evil Saiyans. As a result, he becomes a formidable fighter in his own right under the guidance of Piccolo (the former archenemy of Gohan's father, Goku).
Gohan first masters survival training. He is abandoned for six months in the wilderness, where he must battle hunger, scorpions, saber tigers and dinosaurs, among other things. Next comes intense fighting against Piccolo to train Gohan in the art of war. His mission: "to kill the Saiyans and save Earth." Gohan learns many lessons under Piccolo, such as "don't see the enemy, feel him." Their special bond results in Piccolo stepping in front of Nappa's mighty blast to save Gohan's life.
Initially caught between "wimp" and "warrior," Gohan's loss of nerve in the battle against the Saiyans costs his friends dearly. Haunted by his failure, he is determined to make up for his cowardice. This determination leads Gohan to Planet Namek, where he searches for the source of the original Dragonball so that he can wish his friends back to life. In the end, Gohan comes through in the final battle as he looks at the moon, turns into a Giant Monkey and lunges toward Vegeta, causing him to flee.
Gohan's power when initially kidnapped and placed in the spaceship is 710. It jumps to 1,307 when he sees Goku hurt, then to 28,000 when he goes to fight after Piccolo is injured. His tremendous power is credited to his unique genetic makeup, which makes him a stronger being.