Prescriptive linguistics

Linguistic prescription (or prescriptivism) is the practice of promoting one kind of language use over another. It may imply that some usages are incorrect, improper, illogical, lack communicative effect, or are of low aesthetic value. Sometimes informed by linguistic purism, these normative practices may address such linguistic aspects as spelling, grammar, semantics, pronunciation, and syntax. This approach is often informally called prescriptive grammar, despite its breadth. They may also include judgments on socially proper and politically correct language use.

Linguistic prescriptivism may aim to establish a standard language, teach what a particular society perceives as a correct form, or advise on effective communication. If usage preferences are conservative, prescription might appear resistant to language change; if radical, it may produce neologisms.

Prescriptive approaches to language are often contrasted with descriptive linguistics ("descriptivism"), which observes and records how language is actually used. The basis of linguistic research is text (corpus) analysis and field study, both of which are descriptive activities. Description, however, may include researchers' observations of their own language usage.

Despite being apparent opposites, prescription and description may inform each other, as comprehensive descriptive accounts must take speaker preferences into account, and an understanding of how language is actually used is necessary for prescription to be effective. Since the mid-20th century, English-language dictionaries and style guides – prescriptive works by nature – have been increasingly integrating descriptive material and approaches, beginning (then controversially) with Webster's Third New International Dictionary in 1961, and continuing to the present. For example, new 2010s editions of New Hart's Rules, Fowler's Dictionary of Modern English Usage, and Garner's Modern English Usage have all been updated to add more descriptive and evidence-based material, especially about topics of ongoing conflict between authorities, or in different dialects, disciplines, styles, or registers of usage. Some, like The Chicago Manual of Style, remain primarily prescriptive and traditionalist as of 2017.^[update]

...
Wikipedia