Sociolinguistics is the study of language and how it is affected by the social setting in which language is used. It has a broad scope in its examination of the many and diverse ways that language and society intersect. Sociolinguistics includes not only the study of language and social setting but also psychology and anthropology.
Sociolinguistics examines the interplay of society and language. Clearly, language is affected by the cultural setting in which it is used. For example, in areas of the United States where immigrants from one particular country settled, new words were introduced into the English vocabulary there. In the early 1800s Norwegian settlements began in southeastern Wisconsin and they opened the way for more Scandinavians there and in the Midwest. Because there were no English words for some of the activities pertaining to farming when the immigrants arrived, the Norwegian and other Scandinavian words were used. These words soon became a part of the English vocabulary.
Another aspect of sociolinguistics is the study of dialects, or the regional or ethnic variety of language. For instance, the English dialect
that is taught in schools in the US is Standard American English (also referred to as Edited American English). In such a state as Louisiana, for instance, there are certain parts of the state in which the spoken English has the strong influence of the Acadian dialect (Cajun). Pronunciations also vary in other regions, as do vocabulary and grammatical constructions. Among different socio-economic classes, grammatical constructions sometimes vary. Often the difference in vocabulary and language structure is affected by the level of education of the speaker, but regional differences and bilingualism do factor in as well.
Another significant aspect of sociolinguistics is the contact of languages with one another. In the US, English became the prominent language because it belonged to those who held the most power in the country. French was prominent in Louisiana and was studied in schools throughout the state for a long time, but in the last few decades this custom has changed.
Sociolinguistics is, indeed, an interesting examination of how language and various aspects of society interrelate.