This is one of the more complex questions in all of food-dom. First the easy part, scampi is the plural form of scampo, and since one scampo is never enough for anyone, you almost always hear people say scampi. Now the going gets rough. Scampo is the Italian word for a small lobster that lives in parts of the Mediterranean, the Adriatic, and the North Atlantic from Iceland to Morocco. It is also called the Norway lobster, the Dublin Bay prawn, and the langoustine in France. The Caribbean (or Florida) lobsterette is a close relative.

Now, we could get long-winded and try to answer the questions of what differentiates lobsters from prawns and prawns from shrimp, but (outside the world of marine biology) that depends quite a bit on where you live and is more trouble than it's worth (at least to us). In matters of taste, even within the narrow constraints of the scampi/Norway lobster/langoustine/etc. species, there is a significant difference. Elizabeth David said the Adriatic branch of the family are meatier, have fatter tails, and have much more flavor.

What are the chances that you've actually eaten the real-McCoy scampi? Pretty slim, at least in this country. Generally when you see the word "scampi" on a restaurant menu in Britain, you are getting the real thing, although it is more likely to have been caught in the North Atlantic than near Italy. In this country, the word scampi has been watered down to mean, well, anything a restaurant wants it to mean - generally shrimp sautéed or broiled in butter and olive oil with lots of garlic. You can occasionally find Adriatic scampi in fish markets in this country, but it's a rarity.

For your cooking pleasure, here are two recipes to consider: an authentic Italian scampi recipe from the always reliable Elizabeth David and a traditional American non-scampi scampi recipe from the equally prolific A.D. Livingston.