ELI5: Explain Like I'm 5

Specular reflection

Specular reflection is the kind of reflection that you see when you look in a mirror. It happens when a beam of light hits a smooth shiny surface like glass or water and bounces right back in the same direction. Think of it like bouncing a ball against a smooth wall - the ball bounces back in the same direction it came from. Light works the same way when it reflects off a smooth shiny surface.