ELI5: Explain Like I'm 5

Wave function

A wave function is like a pattern of movement that can roll or wave, like how water makes waves or how light makes wavy paths when it passes through a crystal. It can tell us where particles like atoms and molecules might be in a certain place, but it also tells us how certain they are to be found there. The more wave-like the wave function, the more likely it is that the particle will be in that spot.