The earliest written numbers we know of were used in Egypt and Mesopotamia about 5,000 years ago. At first men reckoned by chipping notches on wood or stone to record the passing of the days. Later the Egyptians wrote on papyrus made from reeds, and the Mesopotamians wrote on soft clay. They used strokes for ones and other marks for tens and up.
Three thousand years later the Romans still made strokes for one to four, but they used new signs in the form of letters for tens, fifties and so on. About the same time, the Chinese used a different sign for every number up to ten, but still used strokes for the first three numbers.
The Mayas in Central America invented the most remarkable system. They used only three signs s dot, a stroke and an oval with these they could write down any number, however large.