The word "yoga" derives from the Sanskrit root yuj ("to yoke"); which is cognate to modern English "yoke", "jugal" and "jugum" in Latin. All derive from the Proto-Indo-European root *yeug- meaning "to join" or "unite".[1] It is generally translated as "union of the individual atma (loosely translated to mean soul) with Paramatma, the universal soul." This may be understood as union with the Divine by integration of body, mind, and spirit. One who attempts yoga may loosely be referred to as a yogi or in Sanskrit, a yogin (masculine) or yogini (feminine), although these designations are actually intended for advanced practitioners, who have already made considerable progress along the path towards yoga. 

Images of a meditating yogi from the Indus Valley Civilization are thought to be 6 to 7 thousand years old. The earliest written accounts of yoga appear in the Rig Veda, which began to be codified between 1500 and 1200 BC but had been orally transmitted for a least a millennium prior to this. The first quasi-rational, full description of the principles and goals of yoga is to be found in the Upanisads, thought to have been composed between 700 and 300 BC. The Upanisads are also called Vedanta since they constitute the end or conclusion of the Vedas (the traditional body of spiritual wisdom). In the Upanisads, the older practice of offering sacrifices and ceremonies to appease external gods gives way instead to a new understanding that man can, by means of an inner sacrifice, become one with the Supreme Being (referred to as Brāhman or Māhātman) -- through moral culture, restraint and training of the mind.

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