Error correction is the set of techniques used to detect, suppress, and repair the noise that makes qubits unstable. Unlike classical bits, qubits are fragile: heat, vibration, imperfect control pulses, and measurement errors can quickly corrupt a calculation. In practice, quantum error correction spreads logical information across many physical qubits so the system can recover from individual failures.
This matters in cybersecurity because useful quantum computers need low error rates to run long algorithms, including some of the cryptographic attacks defenders worry about. If error correction is weak, many proposed quantum threats remain impractical; if it improves, long-lived encryption such as RSA and ECC faces greater future risk. Defenders track error correction as part of quantum readiness, alongside cryptographic inventory, migration planning, and post-quantum cryptography. In real systems, error correction appears both in hardware roadmaps and in operational limits, since every extra correction step costs qubits, time, and reliability.