I’ve heard, from someone who was a Katrina refugee, that what people call “cider” in the South and that which Northerners call “cider” is very different. Here in Michigan (an apple growing region), cider is pressed from the apples and has a bit of ferment beginning, but is not alcoholic – yet. It’s just sweet (but not too sweet), deeply apple-y flavored, and delicious.
Katrina-friend said that what they called cider was more like our apple juice – light colored, kind of bland, and nothing special. In fact, she didn’t know the difference between the two, either, until she came up here and tasted what all the fuss was about.
Cider can go “hard” and become alcoholic. (Apple juice is pasteurized and generally doesn’t harden unless you introduce some yeast into it again.) Once it’s alcoholic, it can change again, into apple cider vinegar (just like any alcohol, gone bad, is vinegar).