Long before Spanish colonization, the indigenous people of Peru kept track of important dates and numbers, and perhaps even stories, using a mysterious coding system of strings and knots called a ...

The absence of modern-day calculators did not stop ancient cultures from performing extraordinary feats of mathematics. The ancient Greeks kept count with abaci, frames with rods or grooves for moving ...

The Inca Empire in South America, one of the most powerful pre-Columbian societies, was known for many innovations — such as the architecture of Machu Picchu, an extensive road network, and a system ...