This document provides an overview of Six Sigma, a disciplined process focusing on improving quality by reducing defects to less than 3.4 per million opportunities. It outlines key concepts such as critical to quality, defect, and process capability, along with two primary methodologies: DMAIC for improving existing processes and DMADV for new product design. Additionally, it describes the roles required for Six Sigma implementation, including champions, master black belts, black belts, and green belts.