by Yannis Ioannidis
Digital Libraries began as systems whose goal was to simulate the operation of traditional libraries for books and other text documents in digital form. Significant developments have been made since then, and Digital Libraries are now on their way to becoming 'Knowledge Commons'. These are pervasive systems at the centre of intellectual activity, facilitating communication and collaboration among scientists or the general public and synthesizing distributed multimedia documents, sensor data, and other information.
Digital Libraries represent the confluence of a variety of technical areas both within the field of informatics (eg data management and information retrieval), and outside it (eg library sciences and sociology). Early Digital Library efforts mostly focused on bridging some of the gaps between the constituent fields, defining `digital library functionality', and integrating solutions from each field into systems that support such functionality. These have resulted in several successful systems: researchers, educators, students and members of other communities now continuously search Digital Libraries for information as part of their daily routines, decision-making processes, or entertainment.
Most current Digital Library systems share certain characteristics. They are content-centric, motivated by the need to organize and provide access to data and information. They concentrate on storage-centric functionality, mainly offering static storage and retrieval of information. They are specialized systems, built from scratch and tailored to the particular needs and characteristics of the data and users of their target environment, with little provision for generalization. They tend to operate in isolation, limiting the opportunities for large-scale analysis and global-scale information availability. Finally, they concentrate on material that is traditionally found in libraries, mostly related to cultural heritage. Hence, despite the undisputed advantages that current Digital Library systems offer compared to the pre-1990s era, the above restrictions limit the role that Digital Libraries can play in Knowledge Societies, which will serve as important educational nuclei in the future.
Together with the general community, the DELOS Network of Excellence on Digital Libraries has initiated a long journey from current Digital Libraries towards the vision of 'Knowledge Commons'. These will be environments that will impose no conceptual, logical, physical, temporal or personal borders or barriers on content. They will be the universal knowledge repositories and communication conduits of the future, common vehicles by which everyone will access, analyse, evaluate, enhance and exchange all forms of information. They will be indispensable tools in the daily personal and professional lives of people, allowing everyone to advance their knowledge, professions and roles in society. They will be accessible at any time and from anywhere, and will offer a user-friendly, multi-modal, efficient and effective interaction and exploration environment.
Achieving this requires significant changes to be made to past development strategies, which shaped the functionality, operational environment and other aspects of Digital Libraries. Knowledge Commons will have different characteristics. They will be person-centric, motivated by needs to provide novel, sophisticated, and personalized experiences to users. They will concentrate on communication and collaboration functionality, facilitating intellectual interactions on themes that are pertinent to their contents, with storage and retrieval being only a small part of such functionality. They will remain specialized systems that will nevertheless be built on top of widely-available, industrial-strength, generic management systems, offering all typically required functionality. In general, they will be managed by globally distributed systems, through which information sources across the world will exchange and integrate their contents. Finally, they will be characterized by universality of information and application, serving all applications and comprehensively managing all forms of content.
There are several key milestones to be achieved on the way towards Knowledge Commons. In particular, a Reference Model for Digital Libraries/Knowledge Commons must be obtained, that is, a framework with a set of interrelated concepts that will collectively capture the essence of the field and help everyone understand its basic elements. An appropriate system architecture (eg Grid or Peer-to-Peer) must also be identified. Other critical steps include devising sophisticated similarity search techniques, handling complex audio-visual content, personalizing user experiences, facilitating semantic interoperation among systems and modelling curation and preservation of content. Research within and outside DELOS is advancing steadily towards these so that a first version may become reality by the end of the decade.
It is serendipitous that, as part of its 'i2010 – a European Information Society for growth and jobs' initiative, the European Commission has recently announced its plans to foster the development of European Digital Libraries, so that Europe's written and audiovisual heritage becomes widely available. This represents a significant step towards Knowledge Commons. Extensive digitization of materials and the formation of many individual Digital Libraries should be followed by incorporation of the latter into a single, universal system that will provide unified access to all content across Europe. This will be the realization of the short-term vision of `The European Digital Library'. If appropriately advanced and openly expandable technology is used, it can also serve as the ideal springboard for realizing the longer-term vision of Knowledge Commons.
"Recommendations and Observations for a European Digital Library (EDL)":
Brainstorming Report, Juan-Les-Pain, France, December 2005
"A Future Vision for Digital Libraries": DELOS Brainstorming Report, Corvara,
Italy, July 2004
"Digital Libraries at a Crossroads", DELOS FP5 Final Report, July 2003
In International Journal on Digital libraries, Volume 5, Number 4, August 2005
ISSN: 1432-5012 (Paper) 1432-1300 (Online) DOI: 10.1007/s00799-004-0098-4,
Pages: 255 - 265, http://www.informatik.uni-trier.de/~ley/db/journals/jodl/jodl5.html
"Digital Libraries: Future Directions for a European Research Program", DELOS Brainstorming Report, San Cassiano, Italy, June 2001:
Yannis Ioannidis, University of Athens, Greece