Scattering theory

Scattering theory is like what happens when you hit a wall with a snowball. The snowball bounces off the wall, but it doesn't come back the same as when it went in. This is like what happens in scattering theory. When particles, like electrons, light, or waves hit something like a wall, they don't come back the same as when they went in. When they hit the wall, they go off in different directions and that is called scattering.