Standard usage includes those words and expressions understood, used, and accepted by a majority of the speakers of a language in any situation regardless of the level of formality. As such, these words and expressions are well defined and listed in standard dictionaries. Colloquialisms, on the other hand, are familiar words and idioms that are understood by almost all speakers of a language and used in informal speech or writing, but not considered appropriate for more formal situations. Almost all idiomatic expressions are colloquial language. Slang, however, refers to words and expressions understood by a large number of speakers but not accepted as good, formal usage by the majority. Colloquial expressions and even slang may be found in standard dictionaries but will be so identified. Both colloquial usage and slang are more common in speech than in writing.

There was a meeting with a large number of people. At first the speaker was very interesting, but as time went on, he became very boring. Finally when he was through, there was only one man sitting in the large room.

¡¡¡¡The speaker walked up to the man and said, "Thank you for hearing me out when all the others left the room."

¡¡¡¡"Oh! Don't mention it!" replied the man, "I cannot leave because I am the next speaker