Since sociolinguistics embraces all studies of language in society, it is many things to many people. But in general we can say, following Wolfram and Fasold 1974, that the field has four main subdivisions. One subdivision is the sociology of language, which studies the effect of large-scale forces on language situations, so it looks at multilingualism and diglossia, language attitudes, language choice, language maintenance, and so on. A second subdivision, given the name ecology of language, deals with the relationship of language to its social environment by considering the application of linguistic knowledge to such practical social concerns as language planning, language standardization, and the solution of educational problems. A third subdivision involves the study of variability, which considers the linguistic and extra-linguistic factors that result in language differences. This area of sociolinguistics has goals similar to those of general linguistics; for example, the nature of linguistic rules and the nature of sound change, but its methods are different. The ultimate aim of variation theory is to provide a sounder empirical base for linguistic theory. The last main subdivision of sociolinguistics, the ethnography of speaking, looks at the relationships between language structure and language function, between referential meaning and social meaning, between language and language use. It analyzes first of all the social context of language and only then begins to look at the ways linguistic resources are organized to serve social ends.