Born: 15 September 973 in Kath, Khwarazm (now KaraKalpakskaya, Uzbekistan), Died: 13 December 1048 in Ghazna (now Ghazni, Afganistan). Ai-Biruni is one of the major figures of Islamic mathematics. He contributed to astronomy, mathematics, physics, medicine and history. His most famous work "India "was written as a direct result of the studies he made while in that country. The "India" is a massive work covering many different aspects of the country. Al-Biruni describes the religion and philosophy of India, its caste system and marriage customs. He then studies the Indian systems of writing and numbers before going on to examine the geography of the country. The book also examines Indian astronomy, astrology and the calendar.