**Leonardo Pisano, who is better known by the name Fibonacci, introduced the Hindu-Arabic number system to Europe at the beginning of the 13th century through his book Liber Abaci, which translates to "Book of Calculation" in English.** It enabled Europeans to break free of the cumbersome Roman numeral system and perform calculations using the decimal system. The talented mathematician was also known for introducing to Europe the number sequence named after him, the Fibonacci sequence.

Because his father was a merchant and stationed by the Italian city-state of Pisa in what is now modern-day Algeria, Fibonacci received an education from the Moors in Northern Africa. This enabled him to see the advantages of the Hindu-Arabic arithmetic system over European methods. He also went further in his studies and sought out the leading Arab mathematical instructors in the Mediterranean area to learn more of their methods. Fibonacci returned from his journeys around 1200, and at the age of 32, he completed his work on "Liber Abaci" in 1202.

The decimal positional system, the use of zero as a place holder, the squaring of fractions and the principles of algorithms were all new mathematical concepts that Fibonacci brought to the European world. He also introduced the Fibonacci sequence, which is intimately connected to the Golden Mean (also known as the Divine Proportion) and represents many of the proportional ratios found in nature. The sequence is also used in art and architecture.