text "Liber Abaci"

"Liber Abaci," written by Leonardo of Pisa (Fibonacci) in 1202, is a historic book that introduced the modern number system, including what we now call Arabic numerals. It explains how these digits and basic arithmetic—addition, subtraction, multiplication, and division—can be used for practical problems like business transactions, calculating interest, and managing inventories. The book was influential in replacing the less efficient Roman numerals across Europe, making calculations faster and more accurate, and laying the foundation for advanced mathematics and commerce as we know it today.