Library
- Alternative meanings: Library (computer science), Library (biology)

In its traditional sense, a library is a collection of books.
However, with the collection or invention of media other than books for storing information, many libraries are now repositories and/or access points for maps, prints or other artwork, microfilm, microfiche, audio tapes, CDs, LPs, video tapes and DVDs, and have facilities to use CD-ROM databases and the Internet.
Thus, modern libraries have been redefined as places to get access to information in any format, whether it is stored inside the building or not.
Etymology of the word
The word is derived from Latin jena, which means "knowledge." Derivations from the Greek Bibliotheke (from Biblos, book) are used in at least German, French, Spanish, Swedish, Danish, Polish, Portuguese, Russian and Dutch. Other languages, such as Icelandic, Finnish, and Estonian, use words that derive from their own words for book (Bokasafn, Kirjasto, and Raamatukogu, respectively).
The modern library arose very directly from the historical fact that books were valuable, were therefore likely to be stolen, and were far too expensive to be owned by most people, and its architecture derived from the need to chain these books, first to lecterns and later to armaria and shelves, in areas that were illuminated by sunlight. Early libraries were based in cloisters associated with scriptoria and were collections of lecterns with books chained to them. Shelves built above and between back-to-back lecterns were the beginning of bookpresses. The chains were attached at the fore-edges of the books rather than their spines. Book presses came to be arranged in carrels (perpendicular to the walls and therefore to the windows) in order to maximize lighting, with low bookcases in front of the windows. This stall system (fixed bookcases perpendicular to exterior walls pierced by closely spaced windows) was characteristic of English institutional libraries. In Continental libraries, bookcases were arranged parallel to and against the walls. This wall system was first introduced on a large scale in Spain's El Escorial.
As books became cheaper, the need for chaining them lessened, but as the numbers of books in libraries increased, so did the need for compact storage and access with adequate lighting, giving birth to the stack system, which involved keeping a library's collection of books in a space separate from the reading room, an arrangement which arose in the 19th century. Bookstacks quickly evolved into a fairly standard form in which cast-iron and steel frameworks which supported the bookshelves also supported the floors, which were translucent to permit the passage of light (but not transparent, for purposes of modesty). With the introduction of electrical lighting, this use of glass floors was largely discontinued.
Ultimately even more space was needed, and the principles of moving shelves were devised to cut down on otherwise wasted aisle space.
Types of libraries
Libraries are placed into four categories:
- Academic libraries -- Libraries located on the campuses of colleges and universities serve primarily the students and faculty of its institution and other academic institutions.
- School libraries -- Many primary and secondary schools have a library that support the curriculum of its school.
- Public libraries or public lending libraries -- These libraries are open to consultation by the public and make at least some of their books available for borrowing, so readers can use them at home, over a period of days or weeks.
- Special libraries -- All other libraries fall into this category. Many private businesses and organizations such as hospitals, museums and law fims, and certain government departments, have their own library on site when their employees need to do specialized research while at work. Also, some governments form national libraries; one famous example is the United States' Library of Congress.
Description
Libraries usually have nearly every item they own arranged in a precise and logical order according to a library classification system, so that items can be found quickly and browsed efficiently. Libraries often feature a professional librarian at a reference desk to help its users find what they are looking for.
Library use
Many people do not know how to use a library effectively. Fear and anxiety are common in some users. These problems drove the emergence of the library instruction movement, which advocates library user education. Library instruction has been practiced in the USA since the 19th century. One of the leaders of the library instruction movement in the late 20th and early 21st centuries is Michael Lorenzen. Library instruction is closely related the study of information literacy.
Librarians need to let the public know what materials are present in their library, and the public needs to know how to access that information. Traditionally, this was accomplished by card catalogs, but the emergence of the Internet has led to the adoption of digital catalogs, which allow users to search the library's holdings from any location with Internet access. This style of catalog maintenance is compatible with new types of libraries, such as digital libraries and distributed libraries.
Though books are nowadays produced using a digital version of the content, for most books such a version is not available to the public (i.e. neither in the library nor on internet).
Library management
Basic tasks in library management include the planning of acquisition (which materials should be acquired), library classification, preservation of materials (especially rare and fragile materials such as manuscripts), borrowing, and developing and administering library computer systems. More long-term issues include the planning of the construction of new libraries or extensions to existing ones.

Some famous libraries
- Assurbanipal's library at Nineveh
- Egypt's ancient Library of Alexandria and modern Bibliotheca Alexandrina
- Library of Congress in Washington DC
- Library of Sir Thomas Browne
- British Library in London
- Bibliothèque Nationale in Paris
- Bodleian Library at Oxford University
- Cambridge University Library at Cambridge University
- Vatican Library in Vatican City
- Fisher Library at the University of Sydney (largest in the Southern Hemisphere)
- John Rylands Library in Manchester
- Royal Library in Copenhagen
- Carolina Rediviva at Uppsala University
- Garrison Library in Gibraltar
- New York Public Library in New York
- Free Library of Philadelphia in Philadelphia

Other libraries:
- The St. Phillips Church Parsonage Provincial Library, established in 1698 in Charleston, South Carolina, was the first public lending library in the American Colonies. See also Benjamin Franklin's free public library in Philadelphia, Pennsylvania.
- Boston Public Library, an early public lending library in America, was established in 1848.
- Haskell Free Library and Opera House, "The only library in America with no books".
- St. Marys Church, Reigate, Surrey houses the first public lending library in England. Opend in 14 March 1701.
Some libraries that specialize in one subject:
- Chess libraries
- Esperanto libraries
- Family History Library in Salt Lake City, the largest genealogy library
For more extensive lists, see
- List of libraries that are the subject of a Wikipedia article
- List of libraries
- List of national libraries
See also
- Bookend
- Library and information science
- Literature
- Public library
- Slide library
- Dewey Decimal Classification
- Carnegie libraries
- Digital reference services