Quote Originally Posted by Shady_arc View Post
Fortunately, in modern language it is very simple: "да" hardly ever means "and", save for a few sayings and set expressions.
Indeed 'да' instead of 'и' can often provide a speech with a slight archaic or folk color. But it is not so obsolete in modern language. Definitely not of 'thou art' level. Sayings and expressions are many rather than few. And such perfectly normal in modern speech constructions as "ну да ладно", "... да еще ..." etc. are more than just archaic set expressions IMO.

The truth is that it usually adds some colloquial and emotional color.