Transform into Super Saiyan
He is the son of Bulma, a tech guru, and Vegeta, one of the most powerful fighters. Trunks is from 7 years in the future. In his time Bulma and himself are the only surviving Z fighters. Powerful Androids created by Dr. Gero are terrorizing his world. Bulma invents a time machine for Trunks to back in time and change the events of history so that they will live in a better world.
When he arrives in the original time, the Earth is being taken over by Freiza and his father King Cold. Because Trunks' power level is much greater than them, he quickly defeats King Cold and Frieza, before the Z fighters even have to break a sweat. He also helps by giving Goku life saving medicine (Goku dies by a heart disease in Trunks' time) and tells the gang of the coming wrath of the Androids.
Trunks comes back 3 years later to help in the battle against the Androids, but to his suprise, the events have changed! Two more androids that Trunks have never seen are now about.
Trunks stays to fight with the other androids, and to compete in the Cell games. He is a brave fighter with a good heart and a passion for fighting.
During the Android Saga, Trunks is born, and then matures to a young child 7 years after the Cell Saga. An interesting feature that Trunks has is the ability to transform into a Super Saiyan at quite a young age. This ability was given to him because trunks was born when his father, Vegeta already was a Super Saiyan at the time when he and Bulma...well you know.
Trunks and Goten become best friends and get into alot of trouble together. Trunks wins the Jr. World Tournament in an impressive fight against Goten.