This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
A scribe worked cuneiform into a wet clay tablet with a cut reed stylus, pressing rather than drawing, which is why every stroke ends in the same wedge shape the script is named for. The earliest tablets from Uruk, around 3200 BCE, were pictographic accounts of grain and livestock, read from the top down in vertical columns. Sometime in the mid third millennium BCE the convention changed: scribes began writing in horizontal rows, left to right, and every sign was rotated ninety degrees from its original orientation. Exactly when and why that rotation happened is still argued over. F. Delitzsch proposed that cursive horizontal writing on clay came first and vertical writing simply persisted longer on stone monuments and statues, a view A. Deimel and A. Falkenstein supported. S.A. Picchioni pushed back, showing that inscribed objects whose orientation can still be checked mostly kept the old vertical arrangement until much later than the rotation theory assumed, well into the Kassite period. Neither side has settled the question. What is certain is that once cuneiform had a syllabic sign inventory alongside its older logograms, it could be picked up by scribes who spoke nothing like Sumerian at all, which is exactly what happened next.