This document explores the crucial role of Micro, Small, and Medium Enterprises (MSMEs) as India's growth engine, contributing significantly to GDP and employment. It details recent developments in MSME classification, including the introduction of a composite criterion based on investment and turnover, and the elimination of distinctions between manufacturing and service sectors. The guide also explains the Udyam Registration process, its mandatory nature for accessing benefits, and its key features, making it essential for entrepreneurs and businesses in India.