The family of lettuce includes hundreds of varieties from tender, buttery soft leaves to crisp, crunchy heads. By far the most common is iceberg lettuce, a head lettuce that is used in salads and sandwiches. Although it is often criticized by some for having little flavor and practically no nutritive value, iceberg continues to be the top seller in the lettuce category. Most supermarkets offer other more flavorful varieties.

The following varieties are the most common in American supermarkets.

• Bibb lettuce is related to Boston lettuce but is smaller, crisper and more expensive.
• Boston is a round, loosely packed head lettuce with soft green leaves. It is sweeter and more tender than any other lettuce. It is sometimes referred to as butter lettuce.
• Iceberg was developed in the 1920's by producers who wanted a less perishable lettuce that would withstand cross-country shipping. It has a mild taste, crisp texture and pale green color. It keeps well.
• Leaf lettuce (red and green) is less sweet than Boston and Bibb. Its soft leaves with curly edges are ideal for sandwiches and make a good addition to salads. The red variety is more fragile than the green, but both can deteriorate quickly.
• Romaine lettuce has elongated heads with dark green outer leaves and lighter, more tender hearts. The leaves are very crisp and sturdy. The dark green color makes romaine more nutritious than any other lettuce.
• Oak leaf lettuce, frisee and chicory are less common salad greens. They are often included as components in baby-lettuce mixes.

Almost all of the major types of lettuce are available all year. Ready-to-eat blends of lettuces and other salad greens are also available in plastic bags.

Select crisp-looking specimens with no signs of rusty color, rot or wilted leaves. All outer leaves of heads should look vibrant and fresh. Iceberg heads should feel slightly springy rather than hard. Leaf lettuce with pale pink on the stems have experienced wet growing conditions and will rot quickly.

1 pound lettuce = about 6 cups of torn leaves.

Store lettuce in the vegetable drawer of the refrigerator. Whether it is washed before storing or just before serving is a matter of choice. The leaves should be dry before storing to discourage mold and rot. If you purchase lettuce from a supermarket that periodically mists vegetables, dry the leaves before storing or add paper towels to bags of damp lettuce to absorb the moisture. Leaf lettuce will keep from two to five days. Iceberg and romaine lettuce lasts five to seven days. Bags of salad mixes are stamped with a freshness date.

Before washing, discard bruised or wilted leaves and remove the central core from iceberg lettuce. Wash lettuce thoroughly under cold running water, taking care to separate the leaves so that any buried mud or grit will be rinsed away. (Soak especially dirty lettuce in water for 5 minutes, then swish to remove dirt.) Drying the lettuce is very important, both for its keeping qualities and so that salads are not diluted by excess water. Salad spinners are invaluable for the job.