The Dragonballs are one of the main themes of the Dragonballs series. Since the begining of the series Goku has always lived around Dragonballs and has always relied on the Dragonballs to resurect his dead allies.
When Bulma arrived to Goku's house Goku already had a Dragonball that he cherished for it was the only significant object that his grand father cherished and passed on to his grand child before dying. When Goku arrived to his house we see that he has put the Dragonball with Four Stars upon a small cushion. He adressed the Dragonball as if he was talking to his grand father telling the Dragonball that he had brought a young women home.
Bulma explains then the legend of the Dragonballs to Goku. The Dragonballs consist in seven yellow-orange balls with red stars inscribed upon them. Each ball has a number of stars going from one to seven. They are undestructable and to people who have no knowledge of what they are they seem like common toys or unvaluble jewlery. But the legend is far more valuble then the apparence of the balls.
When the Seven Balls from earth are gathered together and that a particular sentence is pronounced the sky becomes dark and a humongous Dragon named Shenlon appears in front of the people that invoked the legendary Dragon. The Dragon then tells the people that invoked it that they are alowed to ask him one wish any wish that he will grant. Then once the wish is granted Shenlong disapears and comes back into the Dragonballs which spread themselves afterwards all around the world. For one whole year the Dragonballs will become vulgar rocks and have no value at all.
When the Seven Dragonballs from the planet Namek are gathered around and a different sentence is pronounced in front of them the humongous and very muscular Parunga appears in a dark sky. Puranga on the contrary of Shenlong can grant three wishes but the wishes he can grant have been limited by the great Kaioshin who decided that the wishes can only revive one person at the time and that the wishes can only be granted on the planet Namek. For example if they desire to make something happen on an other planet than the planet Namek the wish can not be granted. However after Freeza destroyed the planet Namek and that he killed the god of Namek, the Dragonballs disapeared. After some years the planet Namek was rebuild and the new god of Namek create different Dragonballs. Indeed their new Dragonballs
can grant three wishes but they can do revive numerous persons at the same time and can grant wishes that can be applied to different planets than Namek.
The DragonBalls with Black Stars are kept in God's palace. These DragonBalls only appear in DragonBall GT and they have the same powers as the other DragonBalls. The only difference is that once used they spread themselves in the whole galaxy and that if they aren't brought back within one year the planet where the Dragon appeared is destined to explode.
Examples of wishes:
1. Revive our friends.
2. Rebuild earth as it was before Cell and the Androids arrived.
3. Revive everybody that died expect the criminals.
