Adi Shankaracharya was an Indian philosopher and theologian who consolidated the doctrine of Advaita Vedanta. He is credited with unifying and establishing the main currents of thought in Hinduism. Shankara traveled across the Indian subcontinent to propagate his philosophy through discourses and debates with other thinkers. He is also known for his commentaries on the Upanishads, Bhagavad Gita, and Brahma Sutras.