Linguistics can be described as all of the following:
Academic discipline – body of knowledge given to - or received by - a disciple (student); a branch or sphere of knowledge, or field of study, that an individual has chosen to specialise in.
Field of science – widely-recognized category of specialized expertise within science, and typically embodies its own terminology and nomenclature. Such a field will usually be represented by one or more scientific journals, where peer reviewed research is published. There are many sociology-related scientific journals.
Social science – field of academic scholarship that explores aspects of human society related to the language it speaks.
Pragmatics – study of how utterances are used in communicative acts – and the role played by context and nonlinguistic knowledge in the transmission of meaning
Applied linguistics – study of language-related issues applied in everyday life, notably language policies, planning, and education. (Constructed language fits under Applied linguistics.)
Biolinguistics – study of natural as well as human-taught communication systems in animals, compared to human language.
Computational linguistics – study of linguistic issues in a way that is 'computationally responsible', i.e., taking careful note of computational consideration of algorithmic specification and computational complexity, so that the linguistic theories devised can be shown to exhibit certain desirable computational properties implementations.
Evolutionary linguistics – study of the origin and subsequent development of language by the human species.
Historical linguistics – study of language change over time. Also called diachronic linguistics.
Language geography – study of the geographical distribution of languages and linguistic features.
Linguistic typology – study of the common properties of diverse unrelated languages, properties that may, given sufficient attestation, be assumed to be innate to human language capacity.
Neurolinguistics – study of the structures in the human brain that underlie grammar and communication.
Psycholinguistics – study of the cognitive processes and representations underlying language use.
Sociolinguistics – study of variation in language and its relationship with social factors.
Stylistics – study of linguistic factors that place a discourse in context.
Semiotics – investigates the relationship between signs and what they signify more broadly. From the perspective of semiotics, language can be seen as a sign or symbol, with the world as its representation.