Sociolinguistics
Sociolinguistics concerns with the investigating the relationship
between language and society with the goal being a better understanding
of the structure of language and how language function in communication
(Wardhough, Ronald, 1986:13). In short sociolinguistics studies the
relationship between language and society. Society has made many
variations of cultures. Then cultures from community to community have
given big impact to language use. 
Further, sociolinguistics has several focus studies. Sociolinguistics
learns about the relationship between language and the context in which it
is used.  Sometimes people use same word in the different social context.
However it will bring different style in language. Different social context
really influences in the using of language. Indeed, people use different
styles in different social context (Holmes, Janet, 2000:1).
Further, another concern on studying of sociolinguistics is
sociolinguistics caused the different types of linguistic variation.
Linguistics variations are used to express social context. The examples of
linguistics variations are word choices, sounds, word-structure and
grammar. Word choices, sounds, word-structure and grammar can be quite
different when they are used in different social context. They are able to
 
convey social information or directive. Again people may use different
pronunciation, vocabulary, grammar or style of a language for different
purposes (Holmes, Janet, 2000:7).
Moreover sociolinguistics has function to describe sociolinguistics
variation and if it is possible to explain why it happens. In other words, the
aim of sociolinguistics is to move towards a theory which provides a
motivated account of the way language is used in a community, and of the
choices people make when they use language (Holmes, Janet, 2000:12). It
means sociolinguistics learn what people should say based on the situation
or context from one community to other communities.