The collective term for the speech and writing habits of a community, especially as they are presented descriptively with information about preferences for alternative linguistic forms. Linguists emphasize the importance of describing the facts of usage as a control on the claims made by grammars, and contrast this emphasis with the prescriptive attitudes of traditional grammar, whose rules often bore no relationship to what people actually did with their language. The many ‘levels of usage’ which descriptive investigations encounter can be formally taken into account in several ways, such as by adding usage labels (as in dictionary entries, e.g. ‘slang’, ‘nautical’), or by the use of statistical statements about preferences, or (in generative contexts) by the notion of variable rules.