Read the excerpt from The Code Book.Just as Whit Diffie predicted in the early 1970s, we are now entering the Information Age, a postindustrial era in which information is the most valuable commodity. The exchange of digital information has become an integral part of our society. Already, tens of millions of e-mails are sent each day, and electronic mail will soon become more popular than conventional mail. The Internet, still in its infancy, has provided the infrastructure for the digital marketplace, and e-commerce is thriving. Money is flowing through cyberspace, and it is estimated that every day half the world's Gross Domestic Product travels through the Society for Worldwide Interbank Financial Telecommunications network. In the future, democracies that favor referenda will begin to have on-line voting, and governments will use the Internet to help administer their countries, offering facilities such as on-line tax declarations.