The Sanskrit word yoga has the literal meaning of "yoke", from a root yuj meaning to join, to unite, or to attach. As a term for a system of abstract meditation or mental abstraction it was introduced by Patañjali in the 2nd century BC. Someone who practices yoga or follows the yoga philosophy with a high level of commitment is called a yogi or yogini.
The goals of yoga are varied and range from improving health to achieving moksha. Within the Hindu monist schools of Advaita Vedanta, Shaivism and Jainism, the goal of yoga takes the form of moksha, which is liberation from all worldly suffering and the cycle of birth and death (samsara), at which point there is a realization of identity with the Supreme Brahman. In the Mahabharata, the goal of yoga is variously described as entering the world of Brahma, as Brahman, or as perceiving the Brahman or Ātman that pervades all things. For the bhaktischools of Vaishnavism, bhakti or service to Svayam Bhagavan itself may be the ultimate goal of the yoga process, where the goal is to enjoy an eternal relationship with Vishnu.