Background & Drivers

Background and Drivers behind the Reference Model

Digital Libraries are a relatively young, highly multidisciplinary scientific field with its roots lying in the last two decades of research and practice. A significant role has been played by funding opportunities supported by the ‘Cultural Heritage and Technology Enhanced Learning’ (formerly ‘Cultural Heritage Applications’) Unit of the Information Society Directorate-General, European Commission and the ‘Digital Library Initiatives’ in the U.S. sponsored by the National Science Foundation and other agencies around the world.

The term ‘Digital Library’ is currently used to refer to systems that are very different in scope and yield very diverse functionality. These systems range from digital object and metadata repositories, reference-linking systems, archives, and content administration systems, which have been mainly developed by industry, to complex systems that integrate advanced digital library services, which have chiefly been developed in research environments. This landscape brings significant impediments, particularly interoperability and the re-use of both content and technologies, which would open up new horizons for the private and public sectors alike and empower a broad spectrum of communities.

The multi-faceted nature of digital libraries has generated a variety of definitions, drawing on different disciplinary perspectives. Fox et al. in (Fox, Akscyn, Furuta, & Leggett, 1995) observe that the expression ‘Digital Library’ evokes a different impression in each person, ranging from the simple computerisation of traditional libraries to a space in which people communicate, share and produce new knowledge and knowledge products. According to Belkin, a Digital Library is an institution responsible for providing at least the functionality of a traditional library in the context of distributed and networked collections of information objects (Belkin, 1999). Lesk analyses and discusses the importance of the terms ‘Digital’ and ‘Library’ in the expression ‘Digital Library’, where the former term mainly implies the existence of software for searching text, while the latter term refers to existing material that has been scanned for online access, and concludes that the research effort in the field is not usually associated with users’ needs (Lesk, 1999). In Borgman’s view, at least two competing visions of the expression ‘Digital Library’ exist: researchers view Digital Libraries as content collected on behalf of user communities, while practising librarians view Digital Libraries as institutions or services (Borgman, 1999). The first DELOS Brainstorming Workshop envisaged a Digital Library as a system that enables any citizen to access all human knowledge, anytime and anywhere, in a friendly, multi-modal, efficiently and effectively by overcoming barriers of distance, language and culture and by using multiple Internet-connected devices (Bertino, et al., 2001). An offspring of that concludes that Digital Libraries can become the universal knowledge repositories and communication channels of the future, a common vehicle by which everyone will access, discuss, evaluate and enhance information of all forms (Ioannidis Y., 2005; Ioannidis Y., et al., 2005). Likewise, in his framework for Digital Library research (Soergel, 2002), Soergel starts from three very diverse perspectives that different people in the community have on Digital Libraries: tools to serve research, scholarship and education; a means for accessing information, and providing services primarily to individual users. He then enhances each one further and binds them all together to obtain the main guiding principles for his vision of the field. On the other hand, Kuny and Cleveland discuss four myths about Digital Libraries (Kuny & Cleveland, 1996): the Internet is ‘The’ Digital Library; at some point there will be a single Digital Library or a single-window view of Digital Library collections; Digital Libraries are means to provide more equitable access to content from anywhere at any time and Digital Libraries are cheaper tools than physical libraries. They conclude that Digital Libraries impose reinvention of the role of librarians and library models.

In addition to such a variety of perspectives that may currently exist on what a Digital Library is, the concept has evolved quite substantially since the early idea of a system providing access to digitised books and other text documents. The DELOS Network of Excellence fostered the view of Digital Libraries as tools at the centre of intellectual activity having no logical, conceptual, physical, temporal or personal borders or barriers on information. Thus the Digital Library has moved from a content-centric system that simply organises and provides access to particular collections of data and information to a person-centric system that aims to provide interesting, novel, personalised experiences to users. Its main role has shifted from static storage and retrieval of information to facilitation of communication, collaboration and other forms of interaction among scientists, researchers or the general public on themes of relevance to the information stored in the Digital Library. Finally, it has moved from handling mostly centrally located text to combining distributed multimedia document collections, sensor data, mobile information and pervasive computing services.

This vision of Digital Libraries seems to echo the concept of ‘Information Space’ that has arisen from the field of Computer Supported Cooperative Work (CSCW). Snowdon, Churchill and Frecon have developed future visions about ‘Connected Communities’ and ‘Inhabited Information Spaces’ (Snowdon, Churchill, & Frecon, 2004), with the latter being closely related to the vision of Digital Libraries, in that ubiquitous information is a prerequisite for CSCW. In more detail, inhabited Information Spaces are ‘spaces and places where people and digital data can meet in fruitful exchange, that is, they are effective social workspaces where digital information can be created, explored, manipulated and exchanged’. Thus, ‘in Inhabited Information Spaces, both information and people who are using that information (viewing it, manipulating it) are represented. This supports collaborative action on objects, provides awareness of ongoing activities of others, and offers a view of information in the context of its use’. Drawing on this and in keeping with the DELOS vision, a Digital Library provides an Information Space that is populated by a user community and becomes an Inhabited Information Space through CSCW technology. In summary, the two fields complement each other, in that one focuses on access and provision of relevant information while the other revolves around visualisation and the sharing of information.

‘Digital Library’ is a complex, multi-faceted notion that defies a simple definition. A comprehensive representation encapsulating all potential perspectives is therefore needed. The Digital Library Manifesto lays down the ground rules by motivating and declaring an organised characterisation of the Digital Library field and by setting an agenda leading to a foundational theory for Digital Libraries. Furthermore, the Manifesto is aimed at facilitating the integration of research and proposing better ways of developing appropriate systems.

The Manifesto explains three types of related systems in the Digital Library universe, namely Digital Library (DL), Digital Library System (DLS), and Digital Library Management System (DLMS). The main concepts characterising these systems and thus the entire Digital Library universe, that is, organisation, content, user, functionality, quality, policy and architecture, are also covered. Professional roles played within digital libraries are chiefly described in terms of end-users, designers, administrators and software developers. Finally, the Manifesto provides the reference framework needed to clarify the Digital Library universe at different levels of abstraction: the Digital Library Reference Model and Digital Library Reference Architecture.