This is part of the Understanding Quantum Information & Computation series. Watch the full playlist here: Building reliable large-scale quantum computers is a monumental challenge, due in large part to the fact that quantum information is extremely fragile. Fortunately, we have a key tool to help in this endeavor: quantum error correction. This lesson takes a first look at quantum error correction, including the first quantum error correcting code discovered — the 9-qubit Shor code — and the foundational concept in quantum error correction known as the discretization of errors. 0:00 – Introduction 2:27 – Overview 3:28 – The need for error correction 5:32 – Classical repetition codes 9:10 – Repetition code for qubits 14:02 – Phase-flip errors 15:13 – Correcting phase-flip errors 18:03 – 9-qubit Shor code 19:34 – Correcting bit-flip errors 21:31 – Errors and CNOTs 23:06 – Correcting phase-flip errors 26:05 – Correcting bit- and phase-flips 28:20 – Random errors 32:06 – Unitary errors 37:16 – Arbitrary errors 39:39 – Conclusion Find the written content for this lesson on IBM Quantum Learning: #qiskit #ibmquantum #learnquantum