The term "digital library" was coined relatively recently and is used to describe distributed access to collections of digital information. The terms "electronic library" and "virtual library" are sometimes also used. However, there is still considerable debate about the definition of a digital library because the term may mean different things to different groups. For example, sometimes it is used to refer to the content or collection of materials ("a digital library of historic photographs"), whereas at other times it refers to the institution or service provided ("the digital library provided electronic reference").

A unique characteristic of a digital library is that it is a collection of material organized for access by the users of the electronic documents. The material is in digital form and may consist of or incorporate various media, such as photographs, video, sound recordings, as well as text and page...