Overview

Today we associate communication technology with high-speed presses and digital computers. However, they are only the most recent of the many ingenious methods people have devised to record and preserve information. The earliest writing surfaces were the walls of caves, where as many as 30,000 years ago images thought to be narratives of hunts or artifacts of archaic spiritual rites were drawn with charcoal and clay slip (a mixture of clay and water). During the next 25,000 years, calendars and inventories were carved into bone and rock. Business and legal transactions, religious texts, and other documents were etched or painted on the walls of public buildings and tombs.

The first materials produced specifically for writing emerged around the fourth millennium B.C., with a corresponding shift from the visual shorthand called...