This document provides an overview of Six Sigma, including its origins at Motorola in 1987 and refinement at GE in 1996. Six Sigma is a quality philosophy and methodology for continuous improvement using statistical tools to create highly accurate processes. It aims to reduce defects to 3.4 per million opportunities. The DMAIC methodology involves defining problems, measuring data, analyzing issues statistically, improving solutions, and controlling processes. The document cites the example of Mumbai Dabbawalas, who deliver 200,000 meals daily with over 99.999999% accuracy, earning them a Six Sigma certification for their supply chain processes.