The document summarizes the evolution and definitions of yoga over thousands of years. It traces the origins of yoga back over 5,000 years to ancient sites in India depicting yoga poses. Yoga developed through four main periods: pre-classical, classical, post-classical, and modern. Key figures like Patanjali systematized yoga into the eight limbs in the classical period. The document also provides definitions of yoga from various ancient texts emphasizing union, stilling the mind, and transcending suffering.