“Writing, according to the latest theories, was invented in southern Mesopotamia for the first and perhaps the only time. The oldest written texts come from Uruk toward the end of the fourth millennium B.C. They were impressed on clay tablets with a reed stylus and then baked. The signs, though linear in form, are no longer purely pictographic, as in some of the preliterate drawings on clay, but considerably conventionalized representations of concrete objects. The new invention must have quickly proved its worth, for it apparently provided the stimlus to the beginning of pictographic writing in Egypt and Persia . . . by about 3000 [B.C.].”

—William W. Hallo & William Kelly Simpson, The Ancient Near East: A History, 1971.