Arabic numerals

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Arabic numerals are the ten symbols 0 through 9 we use to write numbers. They are part of a decimal, place‑value system, where the position of each digit matters. These digits can also be used in other bases or for non-numeric things like license plates or trademarks. They are often called Western Arabic numerals to distinguish them from Eastern Arabic numerals (٠-٩) used in parts of the Arab world.

Origins and names
The digits we use today came from Indian math and were transmitted through the Arabic world. In the east, the Mashriki numerals looked different, while in the west the forms gradually became the shapes we recognize. The symbol for zero came into use as a placeholder and was called sifr in Arabic.

Spread to Europe
Western forms appeared in North Africa and Al-Andalus (Spain) around the 10th century. The spread was gradual. Gerbert of Aurillac (later Pope Sylvester II) helped spread the numerals in Europe in the late 900s. The breakthrough came with Fibonacci, a Pisan mathematician, who popularized them in his 1202 book Liber Abaci after learning the system in Béjaïa (modern-day Algeria). The invention of the printing press in the 15th century accelerated adoption.

Impact and modern use
By the 16th–18th centuries, Arabic numerals were widely used in Europe and gradually replaced Roman numerals for most counting and accounting. Today these digits are used worldwide in everyday writing, science, and computing. They appear in computer encodings such as ASCII and Unicode, making them fundamental to digital text.

Common myth
A popular story claims the shapes were designed to show their value by the number of angles they have. There is no evidence for this, and it doesn’t explain the digits beyond a few.