Upanishads predominantly occur in the last portion of the Vedas and are therefore, also referred to as, Vedanta. The central theme of all the Upanishads is the same, viz., the underlying oneness of Beings and the Lord. Further, the Upanishads also reveal to us – the qualifications that a student needs to have in order to receive this knowledge; the qualifications essential for a teacher imparting this knowledge; the nature of Liberation; how the world is apparent in nature; and so on. Each Upanishad explains these in its own unique way. Upanishads, thus, form the philosophical portion of the Vedas. They are, in general, in the form of a dialogue between a teacher and a student.

Sub topics:

1. Mundaka Upanishad (முண்டக உபநிஷத்)
2. Essence of Mundaka Upanishad (முண்டக உபநிஷத் – சாரம்)
3. Mundaka with Bashyam (முண்டக உபநிஷத் (பாஷ்யத்துடன்))
4. Kena Upanishad (கேன உபநிஷத்)
5. Essence of Kena Upanishad (கேன உபநிஷத் – சாரம்)
6. Katha Upanishad (கட உபநிஷத்)
7. Essence of Katha Upanishad (கட உபநிஷத் – சாரம்)
8. Kaivalya Upanishad (கைவல்ய உபநிஷத்)
9. Essence of Kaivalya Upanishad (கைவல்ய உபநிஷத் – சாரம்)
10. Taittiriya Upanishad (தைத்திரீய உபநிஷத்)
11. Essence of Taittiriya Upanishad (தைத்திரீய உபநிஷத் – சாரம்)
12. Isavasya Upanishad (ஈசாவாஸ்ய உபநிஷத்)
13. Essence of Isavasya Upanishad (ஈசாவாஸ்ய உபநிஷத் – சாரம்)
14. Mandukya Upanishad with Karika (மாண்டூக்ய உபநிஷத் காரிகையுடன்)
15. Essence of Mandukya Upanishad (மாண்டூக்ய உபநிஷத் – சாரம்)
16. Essence of Karika (காரிகையின் சாரம்)
17. Prasna Upanishad (ப்ரச்ன உபநிஷத்)
18. Chandogya Upanishad (சாந்தோக்ய உபநிஷத்)
19. Brhadaranyaka Upanishad (ப்ருஹதாரண்யக உபநிஷத்)
20. Aitareya Upanishad (ஐத்ரேய உபநிஷத்)