We speak differently in different situations. The way we speak and the choice of words depend on the situation in which the processes of communication is realized. As we are speaking about the functions of all this words in different situations we have to define “functional style” Under a “function style” we understand language means peculiar to a specific sphear of communication.
The basic vocabulary is the central group of the vocabulary, its historical foundation and living core.
Basic vocabulary | Informal | Formal | begin | start, get started | commence | continue | go on, get on | proceed | end | finish, be through, be over | terminate | child, baby | kid, brat, beam (dial.) | infant, babe (poet.) |
There has been a diversion between formal and informal speech for nearly as long as language has existed, particularly after the advent of written language, which was initially used in correspondence, business and legal proceedings. Aristocrats also adopted more "high-brow" language also as a way of differentiating themselves from commoners, who were more likely to use colloquialisms in their interactions. Informal vocabulary is used when speaking with friends, relatives, acquaintance. There are several sub-groups in this group:Colloquial words; slang and dialect words
Colloquialisms serve the dual purposes of efficiency and showing familiarity between the speaker and the listener. For example, modern speakers of English often use contractions, such as "how 'd" in "How 'd you do it?" as a faster way of articulating a point than using complete words---"How did you do it?" As a way of expressing closeness and familiarity, friends may say "What 's up?" rather than "How are you?" or the more formal "How do you do?" Colloquialisms can also be found in changes in vocabulary, such as the use of "fave" for "favorite."
Many linguists differentiate colloquial language from slang and other dialects of a language.
References: http://www.bu.edu/mfeldman/Slang/ http://www.webspace.ship.edu http://www.englishclub.com en.wikipedia.org