As small agricultural settlements grew into larger cities connected by trade routes and the Tigris and Euphrates rivers, people needed a way to keep track of goods and transactions. They first used pictographs like this.
Example of the first known writing, 'proto-cuneiform'
This tablet is likely a record of barley distribution.
Gradually, these symbols evolved into a full-fledged writing system. Signs could be logographic (representing whole words or concepts), syllabic (representing syllables, put together to form words), or determinative (markers signalling the presence of a special word like the name of a god). Originally the language was written in vertical columns, but by around 3000 BCE it was read left-to-right and top-to-bottom, like English.
syllabic
logographic
determinative
Sumerian number symbols are easy to recognize.
This is the sign for 6, made up of 2 rows of 3 wedges.
This sign appears on Ex642 as part of the tablet’s date, which tells us these deliveries were made on the 6th day of the month.
Notes & References
Chiera, Edward. Selected Temple Accounts from Telloh, Yokha and Drehem: Cuneiform Tablets in the Library of Princeton University, 1922. Signs cross-referenced with Chiera's normalization.
Electronic Text Corpus of Sumerian Literature. Reproductions made from sign list found here.
Halloran, John. Sumerian Lexicon, version 3.0. https://www.sumerian.org/sumerlex.htm. Logogram dictionary found here.
Image Notes
Proto-Cuneiform tablet: Metropolitan Museum of Art. https://www.metmuseum.org/art/collection/search/329081.
Selene System photographs of Ex642, Firestone Library Digital Imaging.