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.
Engraving
The first evidence for humans engraving patterns is a chiselled shell, dating back between 540,000 and 430,000 years, from Trinil, in Java, Indonesia, where the first Homo erectus was discovered. Hatched banding upon ostrich eggshells used as water containers found in South Africa in the Diepkloof Rock Shelter and dated to the Middle Stone Age around 60,000 BC are the next documented case of human engraving. Engraving on bone and ivory is an important technique for the Art of the Upper Paleolithic, and larger engraved petroglyphs on rocks are found from many prehistoric periods and cultures around the world.