Hinduism is an umbrella term for a range of Indian religious and spiritual traditions (sampradayas) that are unified by adherence to Dharma, a cosmic order maintained by its followers through rituals and righteous living, as expounded in the Vedas. The word Hindu originated as an exonym, and while Hinduism has been called the oldest surviving religion in the world, it is also described since the 19th century by the term Sanātana Dharma. Vaidika Dharma and Arya Dharma are historical endonyms for Hinduism.