Red-tip leaf lettuce has a tender, sweet, delicate flavor that makes it versatile for many types of green salads.
Radicchio is bitter and peppery-tasting when eaten alone, but small amounts add a nice accent to other greens.
Spinach has a mildly hearty flavor and is often used raw in salads.
Swiss chard has large stems with a delicate flavor similar to celery; leaves have a hearty spinach-like flavor.
Romaine has large, crisp leaves and a slightly sharp flavor that make this the classic lettuce for Caesar salad.
Curly endive has a mildly bitter flavor and adds visual interest to salads.
Arugula has a peppery, pungent flavor that is an ideal contrast when mixed with milder greens.