Major or Mukhya Upanishads are twelve in number. Some scholars believe it to be only ten. These chief Upanishads were commented by the great teacher Adi Shankaryacharya. These are considered to be authentic source of ‘Sruti’. Six among the twelve major Upanishad’s details are:
1. Chandogya – It is the oldest Upanishad having the principle philosophy of the Vedas. It has 8 chapters and is associated with Samaveda. The principle philosophy of this Upanishad is oneness of the inner self.
2. Brihadaranakya – This Upanishad is associated with Dark Yajurveda. The Upanishad helps us to know about the actual identity of the inner self.
3. Isa – Shortest among the Major Upanishads. This Upanishad describes nature of Lord (or ‘Ish’.
4. Kena – Kena means- by whom? Hence, this Upanishad is related to who has made this world. This Upanishad is associated with Samaveda.
5. Prasna – The Upanishad Is related to Atharvaveda. There were six sages who asked six questions to the Lord after their long penance. The Upanishad explains answers to the findings of the questions.
6. Taittyiriya – This Upanishad is connected to the Yajurvaveda. The Upanishad describes various modes of happiness and joy in life.
The other Major Upanishads are – Katha, Mundaka, Mandukya, Aitareya, Brahma and Kaivalya.