Quantum error correction

Quantum error correction is a way of making sure that a calculation using a quantum computer is done correctly. It works by taking a bunch of extra "qubits" (the building blocks of a quantum computer) and using them to check if any errors are made during the calculation. When errors are detected, the extra qubits can be used to fix them and make sure that the calculation works like it should. It's like having a special tool that double-checks your work, to make sure it's accurate.