Goku:He is the amin character in the Dragon Ball Z/GT series. He is perhaps the strongest warrior that has ever lived. He learns the fusion, knows the best known attack(Kamehameha)from Dragon Ball Series, what else can I say about him except- He is is an outstanding warrior!!!!!
Vegeta:He is a half evil, half descent person. In the first series-he was evil, but as time progressed his descency increased. He is the second strongest Sayjain.His power level increases almost with every hit. He is a fighter that fights with sayjain honor,strategy, and cool armor!!!
Gohan:At the age of y he was the strongest of them all. He is trained by Piccolo in order to train for the Sayains. Gohan is a very powerful being but is only he is angry. He marries Videl and they have a child named Pan. Later on in Drogon Ball Z- he fights crime and is known as the Great Saijanman!!!
Piccolo- A namekian whom is the strongest alive. He fuses with Nail and Kami making Dende a new guardian of earth. He is in every Dragonball Series. He trains Gohan when they all are training in order to prepare for nappa and Vegeta's Arrival. He is the strongest namek alive........
Family:Every Namek alive
Trunks- He is a freedom fighter from the future. He comes back from the future to warn Goku about the androids that are coming in 3 years. Also to give Goku heart medicine for his future heart atack which takes his life. He kills Freiza and King Cold with his famous sword.
Family:Vegeta-Father Bulma-Mother Bra-sister King Vegeta-Grandpa Dr. Briefs-Grandpa Mrs. Briefs-Grandma
Krillin:Krillin has been Goku's best friend since they studied martial arts together under Master Roshi as kids. He has shaved his head bald so that no one would grab his hair during battle. He also has 6 burn marks on his head, and doesn't have a nose. He is about 1 yr. older than Goku, but is the strongest chrome-dome u ever will meet, also the strongest earthling. He also dies the most times duriing the whole series of Draball z-GT. This shows howstrong u earthlings really r!!
Nappa- Nappa notices Vegetas power in the Bardock Special(when he had hair) and decides to be his bodyguard...kinda. He also looks like a pro wrestler w/saiyan arm. He even kills Tien,Choatzu, and Piccolo, although people say he also kills Yamcha, that was his Saibamens creation. After getting beat up by Goku, Vegeta kills him inorder for Saiyan honor. but in GT, when all hell breaks loose, he escapes, destroys a city, but is returende after a battle w/Vegeta in GT.