Indian mathematics emerged in the Indian subcontinent from 1200 BC until the 18th century. Key classical Indian mathematicians included Aryabhata, Brahmagupta, and Bhaskara II. Indian mathematicians made early contributions to the decimal number system, zero, negative numbers, and trigonometry. These concepts were transmitted to other parts of the world and helped develop mathematics further. Some notable later Indian mathematicians included Bhaskara II, who introduced concepts related to calculus, and Ramanujan, who had a natural genius for mathematics despite a lack of formal education.