Olive oil is made from olives but there are several different kinds to choose from. What do they mean and which is the type for me?
I was always under the impression that extra virgin was the first pressing, virgin was the second, etc. This is what I discovered: All virgin oils are made by physical means only with no chemical treatment. All others use chemicals to extract the oils. So, refined, pure and (plain ol') olive oil are a combination of chemically squeezed and mechanically squeezed oils. The difference between extra and virgin are the acidity levels. Cool, huh?
Olive oils, depending on which type you choose (the more virgin the more expensive) usually have a heavier taste than other vegetable oils so they are great for cooking but not necessarily for baking sweets and definitely not heavy duty frying. These oils are widely used in Mediterranean countries, particularly Greece, and are thought to be the reason they are more heart healthy than residents in the US. That is their claim to fame.
One important aspect of olive oils is storage. Heat, air and light can oxidize the oils, or break down the chemical compounds that make it so healthy. Proper storage (cool, dark place) is imperative to keeping the one year shelf life of these oils. For fire safety never put any oil in a cupboard over a stove or near burners.
No matter what your need or preference, I hope this sheds some light on what's out there, what's healthy, and what's cookin'.