1. DIALECTS
“A dialect is “simply a habitual variety of a language, regional or social. It is set off from all other such habitual varieties by a unique combination of language features…”
Raven I. McDavid, Jr.

2. Regional Dialects in the US: Causes
Borrowings other languages (from Spanish, French, etc)
Language contact (Indians, slaves, other immigrants)
Industrial revolution (move to big cities, new inventions, better mobility)
Trade & immigration (the big cosmopolitan centers influenced other towns). Ex. ‘bird = boid’ (Brooklyn accent = New Orleans)
Environmental Factors (topography, climate, plants, animals, etc). Ex. ‘fresh-water streams.

3. Dialects: How They Differ
The frequent 1st reaction of a person who hears an unfamiliar dialect is that the strange sounds and words are a chaotic mess. This is similar to the feeling an American has when he sees British motorists driving “on the wrong side of the street”.
Roger W. Shuy

4. Languages Don’t “Lack” Anything!
Should we say that in ‘pahk the cah’ the [r] was deleted? Or should we say that in ‘park the car’ an [r] has been inserted?
In order to avoid prejudices, it is better to say: One has the absence of the feature and the other has the presence of it.

5. FINAL COMMENTS
Dialectal distinctive features of other dialects are more noticeable than those of our own dialect
Prescriptive vs Descriptive perspectives
Self-esteem of dialects speakers