Hinduism is an Indian religion and dharma, or way of life, widely practiced in the Indian subcontinent and parts of Southeast Asia. Hinduism has been called the oldest religion in the world, and some practitioners and scholars refer to it as Sanātana Dharma, "the eternal tradition", or the "eternal way", beyond human history. Scholars regard Hinduism as a fusion or synthesis of various Indian cultures and traditions, with diverse roots and no founder. This "Hindu synthesis" started to develop between 500 BCE and 300 CE, after the end of the Vedic period (1500 to 500 BCE), and flourished in the medieval period, with the decline of Buddhism in India.

Although Hinduism contains a broad range of philosophies, it is linked by shared concepts, recognizable rituals, cosmology, shared textual resources, and pilgrimage to sacred sites. Hindu texts are classified into Śruti ("heard") and Smṛti ("remembered").

These texts discuss theology, philosophy, mythology, Vedic yajna, Yoga, agamic rituals, and temple building, among other topics.Major scriptures include the Vedas and Upanishads, the Bhagavad Gita, the Ramayana, and the Āgamas.