The method of conducting sacrifices. There are formed in the way of sutras, which explain how brahmins and mantras are to be used. Each samhita has a specific shrautasutra. For Rigveda samhita, the shrautasutras are Ashvalayana, Shankhayana, Shaunaka, for Samaveda, Mashaka, Latyayana, Drahyayana, for Yajurveda Aapasthamba, Baudhayana, Satyashadha, Hiranyakeshi, Manava, Bharadwaja, Vadhuna, Vaikhanasa, Lougakshi, Maitra, Katha, Varaha, for Shuklayajurveda, Katyayana, and for Adharvaveda, Kaushika. They are a syntax and cannot be understood without interpretation.