In ancient Mesopotamia, it was important to write things down. If you did not know how to read or write, you had to hire someone to write things down for you.  But, you did not have to know how to read or write to sign a contract. Contracts and other written documents were signed with cylinder seals.  What are cylinder seals? (Odyssey Online)  Ancient Cylinder Seals  Free presentations in PowerPoint format  To learn more about Ancient Mesopotamia, click on Gilgamesh