Greatest Discovery: Zero
One of Aryabhata's mathematical discovery was the numeral zero.The indians came up with a number system from one through nine but the main number, zero, came later. Before the zero, people just used a place holder because they did not know what zero was and how it was used. The small yet important number is engraved on a wall in a temple in Gwalior located in central India. By discovering the number zero, he completed the number system.