Writing system
Writing systems were preceded by proto-writing, systems of ideographic and/or early mnemonic symbols. The best known examples are:The invention of the first writing systems is roughly contemporary with the beginning of the Bronze Age in the late Neolithic of the late 4th millennium BC. The Sumerian archaic cuneiform script and the Egyptian hieroglyphs are generally considered the earliest writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3200 BC with earliest coherent texts from about 2600 BC. It is generally agreed that Sumerian writing was an independent invention; however, it is debated whether Egyptian writing was developed completely independently of Sumerian, or was a case of cultural diffusion.
Kish tablet
The writing is still purely pictographic, and represents a transitional stage between proto-writing and the emergence of the partly syllabic writing of the cuneiform script proper. The "proto-literate period" of Egypt and Mesopotamia is taken to span about 3500 to 2900 BC. The administrative texts of the Jemdet Nasr period (3100–2900 BC), found among other places at Jemdet Nasr and Tell Uqair represent a further stage in the development from proto-cuneiform to cuneiform, but can still not be identified with certainty as being written in Sumerian, although it is likely.