Leonardo Fibonacci

Mathematician

Leonardo Fibonacci introduced to Europe and popularized the Hindu-Arabic number system (also called the decimal system). Fibonacci was also known as Leonardo of Pisa. He contributed greatly to number theory, and during his life published many important texts, including Liber abbaci (1202), Practica geometriae (1220) and Liber quadratorum (1225). He is also known for the Fibonacci Series, a numerical series found frequently in the natural world. In the sequence, each number is equal to the sum of the preceding two (1, 1, 2, 3, 5, 8, 13, 21 ...).

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