Browse Books

Reviewer: James Cecil Hammerton

Beyond the familiar term “digital libraries,” there lies an enormous field of related knowledge. A quick scan through the table of contents of this book will caution readers not to embark on a study of digital libraries without at least some preliminary groundwork. An early statement in chapter 1 reads, “A digital library, a collection of information that is both digitized and organized, gives us powers we never had with traditional libraries.” According to the author, “this book explains how to build a digital library.” Lesk pays tribute early on to the foundational work of Vannevar Bush, whose name will be known to many and associated with the scientific efforts of US scientists during World War II.<__?__Pub Fmt eos-space>Likewise, he pays tribute to the innovation of the Colossus, a 1943 machine built and employed by the British during World War II as a code breaker. The book traces the evolution of digital libraries from these early beginnings. The foundation is the ability of computers to manipulate text (no surprise there). The second platform is the ability to manipulate images (not so obvious). The author leads readers in understandable steps, in which he focuses on text searching and retrieval. He cites two kinds of mistakes that a retrieval system can make: errors of omission, in which a retrieval system fails to find relevant documents (“recall failures”); and errors of inclusion, in which nonrelevant documents are retrieved (“precision failures”). These early and basic technologies, and their origins and growth, are fairly well understood. The development of the technologies is less obvious. For example, skewing, or misalignment of a page on a scanner, can be seen as a source of concern. So-called “schemes” are perhaps less obvious sources of error or of additional cost to ensure that they do not destroy the quality of the objects retrieved. Schemes usually consist of figures that may include “chemical structures, spectrograms, equipment diagrams, and so on.” The problem with these items is ensuring that they are appropriately positioned in relation to the typescript that refers to them. After highlighting these problem areas, Lesk describes several less obvious topics. Among them are the inclusion in the library of such items as pictures, as distinct from mere images of printed pages, and sound items in one or more of their many forms. Both images and sound introduce potential complications to item storage, such as color (which may or may not be relevant to the plain text) and voice recognition. Ideally, according to the author, “we should be able to combine information derived from classification, from hypertext links, from text and image researching, and from users. We use all of these sources in today's libraries, albeit informally, and we would like to be able to continue using them in the more mechanical future.” In case readers are still reluctant to acknowledge that digital libraries are a topic in their own right, the sixth chapter considers the problems caused by the function of distribution of materials. Storing and indexing materials are clearly well-<__?__Pub Caret>studied and well-practiced activities of any library. What are the special problems incurred by digital libraries__?__ Such concerns lead up to the problem of how much the extension of normal library functions is likely to cost. Most of us are beginning to get a feel for the reach and the cost of Web-related activities. To those who have spent considerable time and effort mustering and disciplining collections of information for agencies and projecting the cost and the methods of making the data available to authorized users, the advent of the Web appears to have introduced some discernible laxity in today's approach to these essential library functions. Fear not: chapter 10 of this comprehensive text discusses the question of copyright—who owns discrete items of information and how owners can receive remuneration for allowing use of the information. Some thoughts are offered, but the subject is acknowledged to be undeveloped and waiting for someone or some organization to dive in. Chapter 11 describes progress in library systems taking place outside the US.<__?__Pub Fmt eos-space>Much of this activity is sparked by the existence of special collections and by the preservation of special materials. Lesk notes the activities of the British Library's Document Supply Center and its initiative in sending copies of UK publications and doctoral theses to the US. To conclude, the author invokes Shakespeare's seven ages of man, starting with the infant (corresponding to the time when few had even thought about the possibility of electronic library functions). Then comes “the schoolboy corresponding to the initial period of experiments and research in the 1960's. Then the lover, the first flush of excitement about computers and word processors and our ability to put information online.” The soldier, the justice, and the elderly character who can simply use the technology that has been developed, follow. “Finally, we hope, not senility, the last of the Seven Ages of Man, but perhaps the movement of advanced research to new areas” will be the last stage of this development. I am sure that Shakespeare would have been surprised. For those of us who have some familiarity with the subjects addressed in this important book, however, the practical digital library is a wave of the future—firmly set in the work and discovery of the recent past but, more important, destined to have a significant bearing on the technological developments of the future.

Reviewer: Prokop Vondracek

This overview of digital libraries begins with H. G. Wells's dream of a world encyclopedia in which all human knowledge would be available everywhere (1938) and Vannevar Bush's vision of using a keyboard to consult any book (1945). These systems can be built today. The book explains how to build a digital library. It deals with the technology involved in libraries and the problems encountered in gathering and storing information. The author begins with a rough description of the technology involved in libraries, then describes text access methods (which are more interesting to librarians), image storage and manipulation, multimedia storage, and the history of classification and indexing (this chapter may interest computer experts). He then moves on to distribution techniques, the usability of libraries, and how information retrieval systems are evaluated and measured. The book also considers library collection and preservation, collection policy versus accessibility of information by digital means, the economics of digital libraries, and intellectual property rights and their impact on the digital library. It ends with the sometimes neglected topic of various nations' information policies. The very last chapter is devoted to questions about the future and the impact of the growing flow of information, easy information creation, and its easy accessibility to everyone who is interested. This interesting book can be useful in university curriculums as an introduction to the field for students of library science, or as an introduction to library problems and computer applications for students of computer science. It is neatly printed, with many figures and tables.