The Hindu tradition, over the centuries, has recognized eighteen ‘vidyā-sthānas’ or ‘vidyās’, sources of knowledge or sciences. They comprise both the primary and the secondary sources from which we can know ‘dharma’, righteousness, as also duties and responsibilities. They are the four Vedas (Ṛgveda, Yajurveda, Sāmaveda and Atharvaveda), the six Vedāṅgas (Śikṣā, Vyākaraṇa, Chandas, Nirukta, Jyotiṣa and Kalpa), purāṇas, Mīmāṁsā, Nyāya, dharmaśāstras and the four Upavedas (Āyurveda, Dhanurveda, Gāndharvaveda and Arthaśāstra). In some reckonings, Sthāpatyaveda and Śilpa-śāstra (architecture and sculpture) consi-dered as one science, replace Arthaśāstra.
See under each title for the details.