A road usually runs between two more distant points, such as between two towns. A street is described as being a paved road or highway – in a city, town, or village, especially one lined with houses, shops, or other buildings. The implication is that if a street does not have these things, it will probably be called a road. When a town expands, sometimes what was formerly a road will become a street. The word road is the more general term, though, and can be applied to a street. Street is the narrower term.
Above is what I stole from www.dictionary.com A wealth of fun facts can be found there.