William Labov introduced the concept of style in sociolinguistics in the 1960s to refer to typical ways of speaking. Style relates to social factors like the speaker's relationship with the addressee, context, social class, and register. People accommodate their speech styles, such as using more standard forms with unfamiliar people and more casual forms with friends. Accommodation shows politeness and liking, while divergence can be a political message or show social aspirations. Different styles, from vernacular to careful, can be elicited through topic manipulation and social context. Linguistic features indicate both social class membership and contextual variation between styles.