In Hindu philosophy, Brahman is the ultimate reality — the infinite, formless, all-pervading consciousness that is the source and substance of all existence. Brahman is not a deity but the ground of being itself. The Upanishads describe Brahman as "Sat-Chit-Ananda" (existence-consciousness-bliss). All individual souls (Atman) are ultimately one with Brahman, though this unity is obscured by Maya (illusion).