It is important to understand this as it will affect how clinicians evaluate and treat communication disorders. Common language - English is a language common to the United Kingdom, Canada, the United States, and Australia. They have distinct differences, but each member of one culture can communicate with members of a different culture. This has important political-economic ramifications. People feel more closely allied with those who have the most similar communication system.
Dialects are variations within a major language.
Registers - contextual variations across members of a culture. Status - speak differently to peers than to authority figures. Formality - speak differently to people we have just met than to old friends. B. Individual differences - idiolect. Speak most like persons within our own family.