library, traditionally, collection of books used for reading or study, or the building or room in which such a collection is kept. The word derives from the Latin liber, “book,” whereas a Latinized Greek word, bibliotheca, is the origin of the word for library in German, Russian, and the Romance languages.

From their historical beginnings as places to keep the business, legal, historical, and religious records of a civilization, libraries have emerged since the middle of the 20th century as a far-reaching body of information resources and services that do not even require a building. Rapid developments in computers, telecommunications, and other technologies have made it possible to store and retrieve information in many different forms and from any place with a computer and a telephone connection. The terms digital library and virtual library have begun to be used to refer to the vast collections of information to which people gain access over the Internet, cable television, or some other type of remote electronic connection.

This article provides a history of libraries from their founding in the ancient world through the latter half of the 20th century, when both technological and political forces radically reshaped library development. It offers an overview of several types of traditional libraries and explains how libraries collect, organize, and make accessible their collections. Further discussion of the application of the theory and technology of information science in libraries and related fields is included in the article information processing.

The changing role of libraries

Libraries are collections of books, manuscripts, journals, and other sources of recorded information. They commonly include reference works, such as encyclopaedias that provide factual information and indexes that help users find information in other sources; creative works, including poetry, novels, short stories, music scores, and photographs; nonfiction, such as biographies, histories, and other factual reports; and periodical publications, including magazines, scholarly journals, and books published as part of a series. As home use of records, CD-ROMs, and audiotapes and videotapes has increased, library collections have begun to include these and other forms of media, too.Libraries were involved early in exploiting information technologies. For many years libraries have participated in cooperative ventures with other libraries. Different institutions have shared cataloging and information about what each has in its collection. They have used this shared information to facilitate the borrowing and lending of materials among libraries. Librarians have also become expert in finding information from on-line and CD-ROM databases.