Adi Shankaracharya selected ten Upanishads, called Dasopanishads and wrote Bhashya or commentary on them. He highlighted the non-dualist (Advaita) doctrine propounded in them. The Upanishads are commonly referred to as Vedanta. Vedanta has been interpreted as the "last chapters, parts of the Veda" and alternatively as "the object, the highest purpose of the Veda". The concepts of Brahman (ultimate reality) and Atman (soul, self) are central ideas in all of the Upanishads. In this App we have