Quantum corner
Learn qubits step by step, then play with a real quantum simulator. Works offline.
1. What is a bit?
A normal computer bit is like a light switch: it is either off (0) or on (1). Everything on a computer is made of billions of these switches.
2. What is a qubit?
A qubit is a quantum bit. Before you look at it, it can be a mix of 0 and 1 at the same time — like a spinning coin that is not yet heads or tails. That mix is called superposition.
3. Measuring
When you look at a qubit, the spinning coin lands. You get 0 or 1. The mix decides how likely each one is — we call those chances probabilities.
4. Gates
Gates change qubits. X flips 0 to 1. H (Hadamard) makes a perfect 50/50 spinning coin. RY turns the coin a little, so you can choose the chances.
5. Entanglement
CNOT links two qubits: if the first is 1, it flips the second. After H then CNOT, the two qubits always land the same — like magic twin coins.
6. Circuits
A circuit is a list of gates in order, like a recipe. Build one below and watch the chances change. When you are ready, the hypercube router uses four qubits and sixteen corners.
Live simulator
empty circuit — every qubit starts at 0
Try: H on q0, then CX — only |00⟩ and |11⟩ are left. Those are entangled twins.
Game: which coins can land?
Tap every answer you might see when you look. Score: 0
empty circuit · hint: No gates at all.