Quipu

Quipu, also known as khipu, was an ancient Incan system of record-keeping using knotted strings. It employed various knots and colors to convey information, functioning as a complex form of communication. Rather than writing, the Incas used quipu to track data such as census counts, agricultural production, and tribute payments. Each knot's position and type represented different numerical values or categories, allowing for efficient management of their vast empire. Quipu illustrates the Incas' sophisticated approach to information without a written language.