Jemdet Nasr
Apart from the distinctive pottery, the period is known as one of the formative stages in the development of the cuneiform script. The oldest clay tablets come from Uruk and date to the late fourth millennium BC, slightly earlier than the Jemdet Nasr Period. By the time of the Jemdet Nasr Period, the script had already undergone a number of significant changes. It originally consisted of pictographs, but by the time of the Jemdet Nasr Period it was already adopting simpler and more abstract designs. It is also during this period that the script acquired its iconic wedge-shaped appearance.