The Spirit Bomb (元気玉, "Spirit Ball" or "Energy Ball") is a technique performed in the DragonBall series. It is most often associated with Goku, since most users of the move outside of him use it exclusively in video games. The technique was taught to Goku by King Kai.
The Spirit Bomb's size and strength relies on the amount of energy put into it. Goku can request for other living beings to donate energy to it to increase its power; it doesn't matter if it's a person, plant, animal, alien... if it's alive, it can give energy. The Spirit Bomb can also be absorbed by the user, taking its energy into him or herself to power up.