Vocabulary is the area of language least subject to generalization. Unlike the grammar, prosody, and discourse patterns of a language, which are subject to general rules that can be learned thoroughly in a relatively short period of time, the learning of vocabulary is largely ad hoc and of indefinite duration. By contrast with the few hundred points of pronunciation, grammar, and discourse structure which we need to consider when dealing with Shakespeare's language, the number of points of vocabulary run into several thousand. As a result, most books do little more than provide an alphabetical glossary of the items which pose a difficulty of comprehension.The glossary-writers concentrate, as they should, on the difficult words, by which is usually meant words used in Shakespeare that are different from those used today. Either the words themselves have changed (e.g. we no longer use finical) or the meanings of the words have changed (e.g. naughty no longer means ‘evil’). But difference and difficulty are not the same.There are, firstly, some difficult words that are not different (see p. 13). Few students now are familiar with the mythology of Classical Greece or Rome, so the use of such names as Phoebus and Phaeton presents a difficulty. But this is an encyclopedic not a linguistic problem – a lack of knowledge of the world (as it existed in Classical times), rather than a lack of knowledge of how to talk about the world.