In the Dragon Ball Z franchise the Dragon Balls were created by Namekians and they had the power to grant any wish. There are three different sets of Dragon Balls in total. There are the Earth Dragon Balls, Namek Dragon Balls, and Black-Star Dragon Balls. Each set of Dragon Balls can grant wishes, but their power and appearance differ slightly from the other balls. If the creator of a set of Dragon Balls dies, the Dragon Balls will turn to stone and become useless unless they are restored be another Namekian, or the creator is brought back to life.
The Dragon Balls have sometimes appeared as colletable items in video games.
The Earth Dragon Balls were created by the Namekian Kami. These Dragon Balls are small orange balls that can fit in your hand. The dragon that is summoned when you collect all seven balls is called Shenron. Shenron is restricted to only granting one wish at a time and he cannot repeat any wish made before. That fact is basically the whole reason the Z Fighters went to Namek. After the Earth Dragon Balls are used they scatter across the Earth and turn to stone. They remain as stone for an entire year and then become usable. After Dende became the guardian of Earth, he altered the Dragon Balls to make them more powerful. After his alteration Shenron could grant two wishes and if you were done after having only made one wish you can tell Sheron that and the balls will scatter and become usable after only six months.
These Dragon Balls were created by Guru, the leader of Namekian race. These balls are much larger than those of Earth. A normal sized person could only manage to carry two of them at a time. To summon the dragon, Porunga, one must say "Come forth, Porunga" in the Namekian language. Porunga can grant any wish mulitple times and he can grant three wishes per summoning. Although to make a wish you must know how to speak Namekian because that's the only language he understands. As with the Earth Dragon Balls, the Namek Dragon Balls will scatter and turn to stone for a year after use. Unlike Shenron, Parunga can only bring one person back to life per wish.
These Dragon Balls were created by Kami before he became guardian of Earth and still had evil in his heart. These Dragon Balls are about the same size as the Earth Dragons Balls and are very distinguishable because instead of having orange stars they have black stars. These balls can grant one wish and are supposedly a lot more powerful than the Earth Dragon Balls, but they are marked by one defect. When you make a wish with these balls then do not turn to stone and the scatter across the universe, not just the Earth. The worst part is that if the balls are not returned to the planet the wish was made on within a year that planet will exploud. These Dragon Balls are strange in the fact that they do not turn to stone even far after the creators death.