Yoga Darshana Upanishad

Yoga Darśana Upaniśa belodngs to Sāmaveda. It primarily deals with Aṣṭāṅga Yoga philosophy. The main theme of Aṣṭāṅga Yoga is described in it in the form of dialogue between Lord Dattātreya and Sage Sāṅkṛti. 
There are mainly ten khaṇḍas (parts) in it. In the first part the philosophy of the eight limbs of yoga and the ten yamas are described. In the second part the ten niyams are explained. Nine types of asanas are described in the third part. There is a long explanation of introduction to nāḍīs, the pilgrimage to the Self and the glory of the knowledge of Self-realization in the fourth part. Methods of the purification of the nadis and the self-purification are described in the fifth part. Prāṇāyāma, its methods of practice, results and applications are described in the sixth part. Pratyāhāra, its types and results are described in the seventh part. Dhāraṇā and dhyāna are described in the eighth and ninth parts. The state of samādhi and its results are described in the last tenth part. 
Thus, the major subjects of yoga with its vedantic view are presented in this Upaniṣad, which makes it unique and complete.