Over the past decade and a half, free access to computers and the Internet in U.S. public libraries evolved from a rare commodity into a core service. Now, people from all walks of life rely on this service every day to look for jobs, find health care, and read the latest news. As the nation struggled through a historic recession, nearly one-third of the U.S. population over the age of 14 used library Internet computers and those in poverty relied on these resources even more. The library's role as a technology resource and training center has exploded since 1996, when only 28 percent of libraries offered visitors access to the Internet. Internet access is now one of the most sought after public library services, and it is used by nearly half of all visitors. This study provides the first large-scale investigation of the ways library patrons use this service, why they use it, and how it affects their lives. A national telephone survey, nearly 45,000 online surveys at public libraries, and hundreds of interviews reveal the central role modern libraries play in a digital society. Links to appendices (Theoretical Frameworks, Research Methods, Tables, Telephone Survey Instrument, and Web Survey Instrument) are included. (Contains 6 tables, 3 charts, 17 figures, and a list of further readings.)