Quipu - mnemonic device, Inca, Peru, 1400–1534 CE, Camelid fiber and pigment, Gift of Mel Byars, Paris, B08.0787

Although humans have had the ability to speak for dozens of thousands of years, writing only appeared some 5,500 years ago. Developed by the Sumerians in southern Mesopotamia (modern Iraq), it was at first a partial system that was meant to document the transfer of goods — usually to temples. Temple officials needed to keep track of what came in, what was in store, and what came out, and because of the vast quantities and wide variety of supplies and their constant flow, human memory was insufficient to do so. With the invention of writing, they could make one type of marks to represent numerals and another to represent what they wanted to count — people, animals, crops, merchandise, and dates — by making impressions on tablets of damp clay with sharpened bamboo reeds. This early system of writing is known as cuneiform script.

Within a few hundred years, the Sumerians discovered that they could also use script to do many other things — record the King's activities, draw up contracts, tell tales about their gods — and this eventually led to the development of full-fledged writing. Following the Sumerians, many other peoples, including the Chinese, the Egyptians, and the Canaanites, developed their own script, often based on earlier forms of writing. Thus, both the ancient Hebrew and the ancient Greek alphabets belong to the family of Proto-Canaanite script. However, the Quipu writing system of the Andean languages, for example, was developed completely independently of any other writing system, even though Sumerian script had been invented some 2,000 years earlier.