Yoga is a physical, mental, and spiritual practice originating in ancient India with the goal of attaining spiritual insight and tranquility. It is associated with meditative practices in several Eastern religions. Within Hinduism, yoga refers to one of six orthodox schools and is based on Patanjali's Yoga Sutras, focusing on Raja Yoga. Other yoga systems introduced in Hinduism include bhakti yoga, hatha yoga, and karma yoga. The word yoga means "to yoke" or unite, and someone who practices yoga intensely is called a yogi. The goals of yoga range from improving health to achieving moksha or liberation from rebirth.