This glossary is organized by acronym: for example the “Data Encryption Standard” entry says “See—DES.” The “DES” entry contains the definition. This is done because it is the logical approach for a technical book, and allows faster lookups of definitions.
The second reason is to encourage you to learn the mapping of acronyms to terms (and vice-versa). Formal phrases in the Common Body of Knowledge can provide a shortcut to cutting through the clutter in an exam question. Knowing the formal acronyms can provide the fastest roadmap to identifying the crux of a question.
You should understand every term defined in this glossary before taking your exam. A read through of the glossary is a good final exam prep step, as discussed in the “How ...