ELI5: Explain Like I'm 5

Heisenberg's uncertainty principle

Heisenberg's Uncertainty Principle is a rule in physics that states that it is impossible to measure both the position and the velocity of an object at the same time. For example, if you know how fast something is moving, you can’t know exactly where it is at the same time. And if you know where something is, you can’t know how fast it is moving.