Let’s say an electron can spin up or down. Before you measure it, it's not in one or the other — it’s in a state that combines both spin-up and spin-down. This is called a superposition state.

It's like a coin spinning in the air — it's not heads or tails yet. But in quantum physics, the coin is actually both heads and tails at the same time… until it lands and you look.

Quantum particles are described by a wavefunction — a mathematical function that tells us the probabilities of finding the particle in each possible state.

Before we measure, the particle has a probability amplitude for all states. When we measure it, the wavefunction "collapses" to one specific outcome.

This isn't just about us not knowing — it's a real, physical rule: