Fibonacci, known in his day as Leonardo of Pisa, was an Italian mathematician who lived during the Middle Ages. He is widely regarded as the finest mathematician of his age, and although little is known about him, most of us use the contributions of Fibonacci to society every day. In addition to the classical sequence of numbers named after him, Fibonacci also brought the use of Arabic numerals to the West, along with the use of decimal points. These two math features are often taken for granted today, but they were revolutionary in the Middle Ages.
Leonardo of Pisa lived from approximately 1170 to 1250. His father was nicknamed Bonacchio, meaning simple or good, and Fibonacci was nicknamed for his father — Fi'Bonacchi means “son of Bonacchio.” Fibonacci's knowledge of the world was initiated at a young age, because his father was a trader, allowing the son to travel extensively during his youth. Fibonacci's travels undoubtedly introduced him to the Arabic numeral system, along with Middle Eastern math concepts and breakthroughs.
The introduction of Arabic numerals to the West was a major breakthrough. Previously, people used Roman numerals, which were very difficult to work with, especially when complex equations were involved. Fibonacci showed that all numbers could be represented with just 10 digits, and that these digits could be moved and manipulated easily for division, multiplication, and complex equations. This laid the groundwork for modern mathematics.
The Fibonacci sequence is a series of numbers which are mathematically related to each other. Many people know at least the first few numbers in the sequence, which begins with: 0, 1, 1, 2, 3, 5, 8, 13, and continues with each number being the sum of the previous two numbers. The Fibonacci sequence is used to describe a number of phenomena, such as the golden ratio and the tendency of plants to grow in spirals, maximizing their efficiency in a neat Fibonacci sequence. It should be noted that Fibonacci did not discover this sequence, but he does deserve credit for introducing it to the West from India.
During his time, Fibonacci became quite a celebrated figure, thanks to his accomplishments in mathematics and his performance at math games and contests. His most famous work is probably the Liber Abaci, published in 1202. This treatise on arithmetic introduced a number of concepts to the West, along with some intriguing math problems which continue to be posed to students of mathematics today.