This section is for those of you who are new to DBZ or don't know the difference between the two types of Dragon Balls that appear in the DBZ program.
The Dragon Balls are basically the whole point of the DB programs. The Dragon Balls are seven magical balls that when you collect and do the proper chant can grant you any wish you want that is within the dragons power. Once the wish is granted the Dragon Balls are scattered around Earth and have to be collected however you can only make a wish with them once a year.
In DBZ there are 2 types of Dragon Balls Earth's Dragon Balls and the Namekien Dragon Balls Earth's Dragon Balls where created by Kami Earth's god and are quite small. The Earth's dragon is called Shenron and grants one wish that is whiten the creators power. You can only bring someone back to life with Earth's Dragon Balls once however in the Cell saga Kami fuses with Piccolo the Dragon Balls stop working and they need a new God so they get Dende who makes the Dragon Balls more powerful so that he can grant three wishes like Porunga.
The dragon of Nameks Dragon Balls was created by Saichourou the eldest Namek and is called Porunga, he is much larger and more powerfull than Shenron. Porunga can make three wishes and can bring people back to life many times as long as they did not die from natural causes.
To summon the Dragon Balls you need