Electronic libraries must be supported by good software systems that make the data, information, and knowledge accessible. These must have satisfactory functionality, efficiency, and effectiveness. It is an exciting challenge to build such systems, since finding the right information is difficult even for humans.
There are many types of information system, so if we hope to make good progress, we must focus our attention. Since other courses cover DBMS and AI approaches, we concentrate on information access.
This problem can be approached from many directions. We can consider existing systems, like VTLS, see how well they perform, and then see where improvements can be made. We can analyze the overall problem domain, categorizing, classifying, abstracting, and trying to understand the general issues - this is the approach of Chapter 1. We can look underneath, at the fundamental data structures and algorithms, as is done in Chapter 2. Finally, we can look at the research literature, see what approaches have shown promise there, try to understand them, and consider the experimental evidence that shows their possible value - as is done in the Salton article [2].
This Unit works from these several directions, to set the stage for future, more in-depth studies of systems, data structures and algorithms. The student should move back and forth between the two chapters, the VTLS exercise, and the Salton article, till comfortable with the terminology and main concepts.