Also called Vedanta, or 'last part of the Vedas,' the Upanishads were written in Sanskrit between 900 and 500 BC. Part poetry but mainly prose, the earlier Upanishads laid the foundation for the development of several key Hindu ideas, such as connecting the individual soul (atman) with the universal soul (Brahman). Spiritual release, or moksha, could be achieved through meditation and asceticism. The name 'Upanishads' means 'to sit down close,' as pupils did when a teacher recited them.