Each of the Vedas has several Brahmanas and Aranyakas. There are two Brahmanas for Rig-Veda, Aithareya and Sankayana. The Sathappatha Brahmana belongs to Sukla Yajur-Veda. Krishna Yajur-Veda has Thaithreya and Maithrayana Brahmanas. The Thandaya or Panchavimsa, Chhandogya, Adbhutha, Arsheya and Upanishad Brahmanas belong to Sama-Veda. Atharva-Veda has Gopatha Brahmana. They list all the Vedic Karmas or Rituals to be performed and explains how they are to be performed. Each of them has an Aranyaka which explains the inner meaning, the doctrine and philosophy contained in the Samhithas as manthra and in the Brahmanas as Karma. They enlighten us about the Vedas, to understand why Yajnas and Rituals are required to be done. The Upanishads, as the concluding portion of the Vedas, give us the essence of the Philosophy. There were 1081 Upanishads one for each Sakhas of the Vedas. Of all these sections of Upanishads, many of the Sakhas are lost but we have some Upanishads though the related Mantra-Samhita is not available.

The most important Upanishads are: Isa, Kena, Mundaka, Mandukya, Thaithriya, Katha, Chhandogya, Brihadharanyaka, Aitreya, Prasna, Kaushithaki, Svethasvathara and Maithrayani. We also have Maha-Narayana and Bashkala Manthropanishad. Many modern researchers have done laudable works of collecting fragments of more than 16 more Brahmanas and 188 Upanishads. The Four Upa-Vedas are Ayurveda, Dhanur Veda, Gandharva Veda and Arthasasthra. There are Six Vedangas; of which are Siksha and Vyakarna by Panini; Chandas by Pingalacharya and Niruktha by Yaska were explained in an earlier chapter. These four books deal with the language of Vedas and its correct usage and pronunciation. Jyothisha by Garga is a study of Astronomy and Astrology dealing with planetary movements and calculations and their influence on human life and activities. Kalpa is the method of rituals. Of this, we have Srautha, Grihya, Dharma and Sulba belonging to the authorship of various Rishis.

Srautha Suthra explains ritual of Sacrifices. Sulba Suthra gives the measurements necessary for laying out the area for Yajna. Grihya Suthra deals with domestic life and Dharma Suthra deals with ethics, customs and laws. The Prathishakhyas, Padapathas, Upalekhas, Kramapathas, Anukramanis, Daivath sahithas, Parishishtas, Prayogas, Paddhathis, Karikas, Khilas and Vyuhas are further elaboration in the rituals and Karmas of Kalpa Suthras and in the usage of the manthras. Among the Kalpa Suthras, Asvalayana, Sankhyana and Sambhavya belong to Rig-Veda. Katyayana and Paraskara belong to Sukla Yajur-Veda. Aapasthambha, Hiranyakesi, Bhodhayana, Bharadvaja, Manava, Vaikhanasa and Kathaka belong to Krishna Yajur-Veda. Mashaka, Latyayana, Drahyayana, Gobhila and Khadira belong to Saama-Veda. Vaitana and Kaushika belong to Atharva-Veda. This explains to us the slight variations in several rituals performed by various Hindu families. Chanting of Vedas, performance of Yagnas and the rules of discipline are all meant as the preliminaries for the meditation on the true nature of the Self and the Ultimate Reality.

The Secondary canons of Scriptures consist of the Smrithis, which are the ancient Hindu Law codes given to us by the Rishis, based on the teachings of the Vedas. They supplement and explain the ritualistic injunctions and develop the Dharma. They are the Dharma Sasthras that regulate Hindu national, Social, family and individual obligations and duties. There are Eighteen main Smrithis, the most important three being Manu, Yajnavaalkya and Parasara. The other Fifteen are Vishnu, Daksha, Samvartha, Vyasa, Haritha, Sathathapa, Vasishta, Yama, Aapasthamba, Gauthama, Devala, Sankha-Likhitha, Usana, Athri and Saunaka. The laws of Manu are for Sathya [Kritha] Yuga; the Smrithis of Yajnavaalkya are for Thretha Yuga; the codes of Sanakha and Likhitha are for Dwapara Yuga and those of Parasara are written for Kali Yuga. These Smrithis have varied from time to time with different Dharma Sasthras written for each time. They are related to social and emotional surroundings and conditions of the Hindu Society and changes with the time and place.