Reducing the kite's power by shortening its angle of attack — the central safety feature of modern kites.
Depower works on two levels. Short term, you push the bar away: the back lines go slack, the angle of attack drops, and the kite loses pull. Long term, you adjust the depower strap or trimmer above the bar, shortening the front lines relative to the back lines and taking power out of the kite generally — useful when the wind builds. For beginners the practical core is the reflex: when there's too much pull, never pull the bar in, let it out — the depower travel is your built-in brake. And when that isn't enough, use the quick release; a kite is replaceable, you aren't.