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 ...

For more than a millennium, many Andean peoples used an object called a "khipu" (also spelled "quipu" and pronounced "key-poo") to record and communicate information. Khipus were made with cords or ...

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 ...

SAN ANDRéS DE TUPICOCHA starts every year by swearing in new leaders, like many small towns in Peru. Instead of giving the office-holders a sash or medal it gives them a quipu, a coloured skein of ...

Long before computers existed, the Inca people collected data and kept records using knotted strings known as quipu. That technology has inspired a new system for assessing gastrointestinal problems, ...

An Inca quipu (khipu) used for storing data with a system of knots. 15th century CE. Larco Museum, Lima. Credit: Claus Ableiter (CC BY-SA) An Inca quipu (khipu) used for storing data with a system of ...