This document provides an overview of yoga, including its introduction, classification, types, stages, and philosophy. It begins with defining yoga and noting its origins in ancient Sanskrit texts. Yoga is then classified into four historical periods: pre-classical, classical, post-classical, and modern. The types of yoga are outlined, such as Hatha, Ashtanga, Vinyasa, and others. The eight limbs or stages of yoga are described. Finally, the key philosophies of yoga are summarized, such as the concepts of karma and reincarnation.