Gleick begins with the tale of colonial European explorers and their fascination with African talking drums and their observed use to send complex widely understood messages back and forth between villages, and over even longer distances by relay.

Gleick transitions from the information implications of such drum signaling to the impact of the arrival of long-distance telegraph and then telephone communication to the commercial and social prospects of the Industrial Revolution west.

Starting with the development of symbolic written language (and the eventual perceived need for a dictionary), Gleick examines the history of intellectual insights central to information theory, detailing the key figures responsible such as Claude Shannon, Charles Babbage, Ada Byron, Samuel Morse, Alan Turing, Stephen Hawking, Richard Dawkins and John Archibald Wheeler.

Gleick finally discusses Wikipedia as an emerging internet-based Library of Babel, investigating the implications of its expansive user-generated content, including the ongoing struggle between inclusionists, deletionists, and vandals.

"[5] Tim Wu for Slate praised "a mind-bending explanation of theory" but wished Gleick had examined the economic importance of information more deeply.