On what surface did the sumerians write on?

The Sumerians wrote on clay tablets using cuneiform script. Cuneiform is a writing system that uses wedge-shaped marks made with a stylus on clay tablets. The Sumerians used clay tablets because they were widely available and durable. The clay tablets were made by mixing clay with water and then shaping it into a flat tablet. The tablets were then dried in the sun or in a kiln. Once the tablets were dry, they could be written on with a stylus. The stylus was made of a sharp object, such as a reed or a bone. The marks were made by pressing the stylus into the clay. The tablets could be erased by simply smoothing out the clay.