Mesopotamian scribes most commonly used clay for cuneiform tablets.
Fresh clay was abundant in the river plains of southern Mesopotamia, where stone and timber were comparatively scarce. A scribe pressed the end of a cut reed stylus into wet clay to create wedge-shaped impressions. The tablet could then be dried in the sun or, for especially important records, baked hard in a kiln or by fire.
Clay tablets recorded an enormous range of material, including tax accounts, contracts, royal inscriptions, school exercises, legal decisions, letters, medical recipes, myths, and astronomical observations. Their durability is one reason Mesopotamian history is documented so extensively.
Cuneiform was a writing system rather than a language. It was used for Sumerian, Akkadian, and several other languages across many centuries. The word “cuneiform” comes from the Latin cuneus, meaning “wedge,” describing the appearance of the impressions rather than the clay itself.