9. **Upanishadic Literature**: There are over 200 Upanishad…

9. **Upanishadic Literature**: There are over 200 Upanishads, but traditionally, about ten or twelve are considered principal:
- Upanishads like Brihadaranyaka, Chandogya, Taittiriya, Aitareya, Kaushitaki, and others are the most prominent and contain some of the densest philosophical discussions.