This animation shows a ball bouncing down a nonlinear slope. When the ball hits the slope, NDSolve automatically stops the computation, resets the conditions for bouncing off, and restarts.

Event detection enables differential equations to be solved differently in different regions, with boundaries between regions determined dynamically by features of the solutions obtained. This feature's flexibility is a unique capability of Mathematica.

Typical applications include:

	Modeling hybrid systems with physical constraints where an event triggers swapping between different regimes
	Solving only until some logical or functional condition is satisfied
	Collecting samples of solutions at particular events, or for Poincaré sections