In comparison to traditional libraries, digital libraries provide efficient and qualitative services by collecting, organizing, storing, disseminating, retrieving and preserving the information. Digital libraries support preservation besides making information retrieval and delivery more comfortable. It provides online access to historical and cultural documents whose existence is endangered due to physical decay. The major areas which offer digital libraries great exploitation are: Information retrieval, multimedia database, data mining, data warehouse, on-line information repositories, image processing, hypertext, World Wide Web and Wide Area Information Services (WAIS). Digital libraries necessarily include a strong focus on the management of digital content, just as traditional libraries have focused for long on the management of content in physical forms. Most of the digital content that is being managed includes human language, either in the form of character-coded electronic text, scanned versions of printed or handwritten text, or digital representations of human speech. Language technology therefore plays a major role in managing digital content. This comes as no surprise, of course. Digital libraries today make good use of what we know about searching large collections, and techniques such as machine-assisted indexing are employed increasingly often as we strive to extend our reach to progressively larger collections. But we are on the verge of a new era, one in which our machines will learn from what we do and then apply those capabilities to enable the management of digital content at a far larger scale than we could ever hope to do ourselves. Few advantages of digital libraries according to Haddouti are:User can access the information anywhere Reduces bureaucracy by providing access to the information The information is not necessarily located in same place Understanding the catalogue structure is not necessary Cross references to other documents speed up the work of users Full text search Protected information source Wide exploration and exploitation of the information The knowledge dissemination is an integral part of the success story of the popularity of creating digital libraries. The aim is to provide universal access to human knowledge, and given the advancement of digital storage and communications this goal is now achievable.