The first thing to consider when purchasing olive oil is how you plan on using it in the kitchen. Appropriate for a variety of cooking methods, from roasting and deep-frying to sautéing and baking, it can also be used as a salad dressing or topping. Based on the culinary application you have in mind, you can choose from these three common varieties, available at most grocery stores.

• Extra-virgin olive oil: Derived from the first press of olives, this oil boasts the most full-bodied flavor. It can be used for all forms of savory cooking, including sautéing, stir-frying, roasting and marinating, and is the best choice for bread dipping and salad dressing.
• Olive oil: Also known as "pure," it's typically milder than extra-virgin and more yellow in color. While not quite as high-quality as extra-virgin, it's great for savory cooking and adds flavor and depth to a dish.
• Extra-light olive oil: For this oil, the term "light" does not apply to its nutritional makeup but rather to the oil's color, texture and flavor. The mildest of all the oils, it's best for baking and savory cooking at very high temperatures.