As a physical object.
A tablet is a physically robust writing medium, suitable for casual transport and writing. Clay tablets were flattened and mostly dry pieces of clay that could be easily carried, and impressed with a stylus. They were used as a writing medium, especially for writing in cuneiform, throughout the Bronze Age and well into the Iron Age. Wax tablets were pieces of wood covered in a thick enough coating of wax to record the impressions of a stylus. They were the normal writing material in schools, in accounting, and for taking notes. They had the advantage of being reusable: the wax could be melted, and reformed into a blank.