It took people thousands of years to write down nothing.

Zero does two jobs. The first is holding a place: without a mark for an empty column, 205 and 25 look the same. With that one mark, ten digits are enough to write any whole number, and the same column-by-column methods work for adding, multiplying and dividing on paper.

The second job is being a number in its own right. Zero is what you get when you take a number away from itself. It sits between the positive and negative numbers, and it made modern algebra possible.4

People wrote numbers long before anyone wrote a zero. Babylonian scribes began using a mark for an empty place around 400–300 BCE. The Maya came up with a zero of their own, likely in the first few centuries CE, with no contact with the Old World.1 Both used it as a placeholder rather than a number you could calculate with.4

In India, a dot marked the empty place, and that dot later grew a hollow center: the 0 we write today.2 The Bakhshali manuscript, a mathematics text on birch bark, is full of these dots. Radiocarbon tests in 2017 dated its oldest leaves as early as the 3rd or 4th century CE,2 although historians of Indian mathematics argue that the text as a whole is younger.3

In 628 CE the astronomer Brahmagupta wrote the earliest known text that treats zero as a number.2 He gave it rules, writing about positive and negative numbers as fortunes and debts: adding or subtracting zero changes nothing, multiplying by zero gives zero, and taking a debt away from zero leaves a fortune.4

He also said that zero divided by zero is zero. Mathematicians today leave that question undefined, which shows how hard nothing is to pin down.4

Zero and the Indian numerals traveled west through the Islamic world. Leonardo of Pisa, known as Fibonacci, learned them as a young man in Bugia, in present-day Algeria, where his father ran a trading post.5 His 1202 book, Liber Abaci, presented the ten digits, zero included, to European readers.5 Not everyone welcomed it: some cultures distrusted zero for its almost magical air.1

Counting from the Babylonian placeholder, the idea took about 1,500 years to become a number, and another 600 to reach a European book.

A QR code is a grid of dark and light squares. Your phone reads each dark square as a one and each light square as a zero, so every code on this wiki is a picture of ones and zeros, including the code on this page.

Georges Ifrah (1947–2019) spent years following numbers across cultures. His book From One to Zero: A Universal History of Numbers came out in English in 1985. A later, expanded edition is The Universal History of Numbers: From Prehistory to the Invention of the Computer (Wiley, 2000).6