Full context:   The Taittiriya Upanishad describes five koshas, which are also often equated with the three bodies.[by whom?] The three bodies are often equated with the five koshas (sheaths),[by whom?] which cover the Atman: The three bodies are an essential part of the Yoga physiology. Yoga aims at controlling the vital energies of the bodies, thereby attaining siddhis (magical powers) and moksha.