Shankara lived only thirty-two years but produced commentaries on the principal Upanishads, the Bhagavad Gita, and the Brahma Sutras that became the definitive statement of Advaita Vedanta. He established four monastic centers across India that still anchor the tradition today.
His central teaching: Brahman alone is real; the world, as ordinarily seen, is a superimposition; liberation is the recognition that one has never been other than Brahman.