ELI5: Explain Like I'm 5

Reflection (physics)

Reflection is a physics concept that explains how light and sound bounce off any surface. For example, when you're outside and hear birds singing, the sound waves are bouncing off trees and other surfaces before reaching your ears. Reflection also explains how you can see yourself in a mirror - the light from your face bounces off the mirror, so you can see a reflection of yourself in it.