This document discusses the concept of poka-yoke, or mistake-proofing, which aims to prevent human and machine errors in processes. Poka-yoke was formalized by Shigeo Shingo as part of the Toyota Production System. It involves implementing fail-safe methods that detect or prevent errors at their source. There are different types of poka-yoke including prevention and detection devices. It is important as it helps improve quality and reliability by driving defects out of products and processes. Poka-yoke can be applied wherever errors may occur and includes techniques to prevent or highlight errors.