The Upanishads are ancient Sanskrit texts that contain some of the central philosophical concepts and ideas of Hinduism, some of which are shared with religious traditions like Buddism and Jainism.
The Katha Upanishad is one of the primary Upanishads which was embedded in the last short eight sections of Katha school of the Krishna Yajurveda.
The well-known dialogue between Nachiketa and Yama is mentioned in Kathopanishad.

