Rapid advances in information technologies have revolutionized the role of libraries. As a result, libraries face new challenges, competitors, demands, and expectations. Libraries are redesigning services and information products to add value to their services and to satisfy the changing information needs of the user community. Traditional libraries are still handling largely printed materials that are expensive and bulky. Information seekers are no longer satisfied with only printed materials. They want to supplement the printed information with more dynamic electronic resources. Demands for digital information are increasing.
Digital libraries will start gaining ground in India in the present century. We are heading toward an environment in which digital information may substitute for much print-based information. A library's existence does not depend on the physical form of documents. Its mission is to link the past and the present, and help shape the future by preserving the records of human culture, as well as integrating emerging information technologies. This mission is unlikely to change in the near future.
Digital libraries come in many forms. They attempt to provide instant access to digitized information and consist of a variety of information, including multimedia.
A digital library is a library in which collections are stored in digital formats (as opposed to print, microform, or other media) and accessible by computers. The content may be stored locally, or accessed remotely. The first published use of the term may have been in a 1988 report to the Corporation for National Research Initiatives. The term was first popularized by the NSF/DARPA/NASA Digital Libraries Initiative in 1994. Bush (1945) created a vision based on experience ("Digital library.")
The Digital Library Federation defines digital libraries as:
Organizations that provide the resources, including the specialized staff, to select, structure, offer intellectual access to, interpret, distribute, preserve the integrity of, and ensure the persistence over time of collections of digital works so that they are readily available for use by a defined community or set of communities. (Shiri 2003)
The DELOS Digital Library Reference Model defines a digital library as:
An organization, which might be virtual, that comprehensively collects, manages and preserves for the long term rich digital content, and offers to its user communities specialized functionality on that content, of measurable quality and according to codified policies. ("Digital Library")
A digital library is not a single entity. It requires technology link the resources of many collections. The links between digital libraries and their resources are transparent to users. Digital library collections are not limited to document surrogates (bibliographic records. They are the actual digital objects such as images, texts, etc.
Lynch (1994) says that, "digital Libraries ... [provide] users with coherent sccess to a very large, organized repository of information and knowledge." According to Berkeley Digital Library Project, University of California, the digital library will be a collection of distributed information sources. The contrast between traditional and digital libraries is presented below
Traditional Libraries Digital or Electronic Library Print collection All resources in digital form. Stable, with slow evolution Dynamic and ephemeral Individual objects not directly Multi-media and fractal objects linked with each other. Flat structure with minimal Scaffolding of data structures contextual metadata and richer contextual metadata. Scholarly content with More than scholarly content with validation process various validation processes Limited access points and Unlimited access points, centralized management distributed collections and access control The physical and logical The physical and logical organization organization correlated. …