You will gain first hand experience with the concepts explored in the first chapters of the text, especially about words, index terms, thesauri, and their relationship to retrieval systems.
Regarding words, the English lexicon, query expansion, and general related terms for common words, WordNet is the best widely available vehicle for explanation. After exploring WordNet, you will become familiar with the most widely used classification system, the Dewey Decimal Classification (DDC). To gain more of a discipline specific understanding, you will work with ACM's Computing Classification System (CCS). With that as background, you will see how a medical thesaurus (MeSH) has been expanded into a larger Metathesaurus, and how they are used in some advanced retrieval systems of the National Library of Medicine, Grateful Med and PubMed.