Although eggplant is generally thought to be a vegetable, it's acutally a fruit--specifically, a berry! Ranging in color from deep purple to white, and in size from miniature to large, eggplant comes in many varieties. The most commonly available eggplant is large, cylindrical or pear shaped with smooth, glossy purple skin.
Choose eggplant that has firm, smooth skin and feels heavy for its size. Avoid any with soft, wrinkled or brown spots. Store eggplant in a cool, dry, dark place, using it within a day or two of purchase before it becomes bitter.
Eggplant should be cut just before cooking or serving, since the flesh discolors rapidly. If eggplant is young, the skin doesn't need to be peeled.