Ki is a special technique used throughout the Dragonball series. It means "Life-force" in English. Ki is what you see in Dragonball almost every time you watch it. When the characters fly, throw energy balls, and glow, this is all ki power. Ki can also be used to sense another's ki force. A character can detect if someone is strong or weak, good or evil, and if they are hurt or in good shape. Scouters used in the Saiyan Saga, detect someone's power level, which is basically someone's ki. Ki can also be used as a technique. For example, Goku's Kamehameha, is a ki technique.