Tallies to Symbols

The oldest known math artifact is a 35,000-year-old baboon bone with 29 tally marks — possibly tracking lunar cycles. Tally marks were humanity's first numbers: one mark per object. Simple, but clumsy once the count grows large. Try writing 1,000 as tally marks and you will feel the problem.

Civilizations independently invented numeral systems to solve this scaling problem. The Sumerians used base-60 (which is why we have 60 minutes in an hour). The Mayans used base-20. The Babylonians developed place-value notation — the idea that a digit's position affects its value.