The most important scriptures common to all Hindus are the Vedas, the Upanishhads and the Brahma Suutras. The Vedas are called Shruti, literally that which is heard. Those that believe the Vedas to be the supreme authority for Hinduism are called ãstikas, and those that do not are nãstikas. (Popular misnotion is that ãstikas are believers (in God) and nãstikas are atheists). Allowing for poetic license, it can be interpreted as that which is discovered. Smruti, on the other hand, is what is remembered, effectively that which was told. Shruti is unalterable because it is a record of observations and experiences. The scriptures explaining the various forms of manifestations of the Divine and details of worship for Them is called the Agamãs. Directly or otherwise, the Upanishhads constitute the philosophical framework for Hinduism. Every religious movement that arose within Hinduism has had to show itself to be in accordance with the Upanishhads. The philosophical treatises that explain the message of the Vedas and Upanishads is called Dharsanas.

Shrutis are Divine revelations. Smrutis, on the other hand, are entirely artificial created as an interpretation of the Vedic texts, and ethical codes of conduct, and hence warrants modification with changing times and increasing finesse of knowledge. Since theory should fit observation, and not vice versa, Smruti is of secondary authority. All matters relating to the Hindu Legal Code fall under the category of Smrutis and are thus designed for change. Then there are other ancients texts of imporatance. They include the Epics, which are the stories based on the philosophy, ethics, codes of law and the sacred romances. The Bhagavadgita is said to be the essence of the Upanishhads for the layman, and is revered by all sects. The epics called Ithihãsãs[meaning "It happened thus"], RaamãyaNa and Mahãbhãrata and the Bhãgavata Purãna and other Purãnãs [meaning old history] are, texts or historical treatises explaning the Hindu tenets and ethics. Countless generations have been molded by the ideals set for them in these epics. Thus it is that with the Vedas, the Upanishhads, the RãmãyaNa, the Mahãbhãrata, the Bhagavadgita and other sacred writings deriving their authority from the Vedas, the scriptures of Hinduism are a strong force making for unity within all diversity of beliefs and practices.

Based on these holy texts, later religious leaders gave the various texts of theories to explain the practical aspect of the faith for the followers. Vedas Vyasa or Bhãdarãyana gave the Vedhãnta philosophy and Dharma Sãstra, which along with the teachings of other ancient saints, was interpreted later by several Ãcharyãs as Advaita by Sri Sankara, Visishta-advaita by Sri Ramanuja, Dwaitha by Sri Madhva and several others similar interpretations by other leaders. These later day texts formed the essence of the Hindu faith, along with the teachings of the purãnãs, Ãgamãs and worship of various forms and manifestations of God, as it is practiced in modern times. These texts based on the Vedas, Upanishads and Dharma Sãstrãs gave us the basis for Hindu ethics and practice as a way of life. The heterodox faiths that do not accept the Vedas as the Holy Scriptures, such as Buddhism and Jainism splintered away from mainstream Hindu faith.