Hinduismis also known as Sanātana Dharma (सनातन धर्म), a Sanskrit phrase meaning "the eternal law". It is a religion that originated in the Indian subcontinent, and often stated to be the "oldest religious tradition" or "oldest living major tradition." It is formed of diverse traditions and types and has no single founder.
The first collection of Indian philosophy that was written down was the Vedas. The word 'Veda' comes from the Sanskrit vid, meaning knowledge - the Vedas are 'sacred knowledge'. Their exact date is controversial, it is believed that the knowledge dates back 10,000 years BC, and were first written around 3,000 BC.
The metaphysical foundation of Hinduism, which is expressed in both the Vedas and the Upanishads is that Reality (Brahman) is One or Absolute, changeless, perfect and eternal. The ordinary human world of many separate and discrete (finite) things (which our mind represents by our senses) is an illusion. Through meditation and purity of mind, one can experience their true Self which is Brahman, God, the One infinite eternal thing which causes and connects the many things. True enlightenment is Self-realisation, to experience the supreme reality as Self.
Hindu beliefs vary widely, with concepts of God and/or gods ranging from pantheism to polytheism, with Brahman, Vishnu and Shiva being the most popular deities. Other notable characteristics include a belief in reincarnation and karma, as well as personal duty, or dharma.
Hinduism's vast body of scriptures is divided into Śruti ("revealed") and Smriti ("remembered"). These scriptures discuss theology, philosophy and mythology, and provide information on the practice of dharma (religious living). Among these texts, the Vedas and the Upanishads are the foremost in authority, importance and antiquity. Other major scriptures include the Tantras, the Agama, the Purāṇas and the epics Mahābhārata and Rāmāyaṇa. The Bhagavad Gītā, a treatise from the Mahābhārata, spoken by Krishna, is sometimes called a summary of the spiritual teachings of the Vedas.