It is important to note that although many linguists may use the term "corpus" to refer to any collection of texts, when it is used here it refers to a body of text which is carefully sampled to be maximally representative of the language or language variety. Corpus linguistics, proper, should be seen as a subset of the activity within an empirical approach to linguistics. Although corpus linguistics entails an empirical approach, empirical linguistics does not always entail the use of a corpus.
In the following pages we'll consider the roles which corpora use may play in a number of different fields of study related to language. We will focus on the conceptual issues of why corpus data are important to these areas, and how they can contribute to the advancement of knowledge in each, providing real examples of corpus use. In view of the huge amount of corpus-based linguistic research, the examples are necessarily selective - you can consult further reading for additional examples.