Cuneiform, from the Latin word cuneus (wedge), is the term used to describe the earliest known writing. The advent of writing and its subsequent evolution is not clearly known. It is not known if the invention of writing was the act of a single genius, an effort by a group of people, or was the result of a slow process. A popular theory involves the use of three-dimensional clay tokens. These clay tokens were pressed into wet clay. Eventually scribes began to draw two-dimensional shapes into the clay to represent the tokens.
Whatever the evolution, by 4000 B.C. the Sumerians developed a form of pictograph writing. Early pictograph writing had several disadvantages. Early pictographs could not express abstract ideas, only physical objects. Some of the symbols were too complicated to draw with the writing instruments the scribes had available to them. Lastly, there were no standards leading to great variation between the many pictographs in use. This would lead into the next evolution of writing.
To overcome the limitations imposed by a pure pictograph script scribes began to develop phonetics. For example, the words for "bee" and "leaf" could be combined to form "belief." Over time the pictographs became stylized and shortened into wedge-shaped imprints allowing syllables to be formed instead of pictures and allowed the script to become standardized. By 3000 B.C. cuneiform was developed.
Cuneiform was initially utilized for accounting purposes. Transactions were recorded on clay tablets and were sometimes sealed in clay envelopes to protect against fraud and tampering. The Sumerian cuneiform script became the standard script for Mesopotamia as it was adopted by the Akkadians, Assyrians, Babylonians, and spread as far as Persia and Egypt. Cuneiform proved to be a very resilient script. It would undergo several transformations over the ensuing centuries and it could still be found in use in astronomical charts as late as 75 A.D.