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.