According to what I've read, to Adi Shankara, God, the Supreme Cosmic Spirit or Brahman (pronounced as brahman; nominative singular Brahma, pronounced as brahma, is the One, the whole and the only reality. The transcendental or the Pa-rama-rthika level in which Brahman is the only reality and nothing else.
"Adi Shankara claims that the world is not absolutely false. It appears false only when compared to Brahman." http://en.wikipedia.org/wiki/Advaita_Vedanta
