Before anyone wrote a sentence, someone in Uruk wrote a table. Sumerian administrative tablets are palm-sized slabs of river clay, ruled into columns and horizontal registers with a straightedge before a single sign was pressed. Barley, sheep, rations, names, totals — each locked to a rule.

This system takes the tablet literally. The page is clay, not paper. Type sits in the surface rather than on it, dividers are scored grooves with measurable width, and the ledger grid carries the layout instead of decorating it. It is the oldest data design we still have, used as a data design.