Accordingly, functional styles are classified into two groups, with further subdivisions depending on different situations.
Informal vocabulary is used in one's immediate circle: family, relatives or friends. One uses informal words when at home or when feeling at home.
Informal style is relaxed, free-and-easy, familiar and unpretentious. But it should be pointed out that the informal talk of well-educated people considerably differs from that of the illiterate or the semi-educated; the choice of words with adults is different from the vocabulary of teenagers; people living in the provinces use certain regional words and expressions. Consequently, the choice of words is determined in each particular case not only by an informal (or formal) situation, but also by the speaker's educational and cultural background, age group, and his occupational and regional characteristics.
Informal words and word-groups are traditionally divided into three types: colloquial, slang and dialect words and word-groups.
Among other informal words, colloquialisms are the least exclusive: they are used by everybody, and their sphere of communication is comparatively wide, at least of literary colloquial words. These are informal words that are used in everyday conversational speech both by cultivated and uneducated people of all age groups. The sphere of communication of literary colloquial words also includes the printed page, which shows that the term "colloquial" is somewhat inaccurate.
Vast use of informal words is one of the prominent features of 20th century English and American literature. It is quite natural that