This document provides an introduction to sociolinguistics. It defines sociolinguistics as the study of the relationship between language and the social contexts in which it is used. It discusses key topics in sociolinguistics including language and dialect, regional dialects, social dialects, and language styles, registers, and beliefs. Regional dialects are varieties of a language that differ based on features of phonology, grammar, and vocabulary between geographical areas. Social dialects vary between social groups and are influenced by factors like social class, religion, and ethnicity. Language styles and registers refer to the ways language is used in different social settings or occupations within a community.