Herbs are the leaves, stems, or flowers of aromatic plants, used fresh or dried to add flavor, aroma, or color to dishes. The term is usually distinguished from a spice, which comes from a plant's seeds, bark, roots, or other non-leafy parts; a few plants, such as coriander, supply both, since the leaves are used as the herb and the seeds as the spice.
Herbs have been used to season and preserve food for thousands of years across nearly every cuisine, from Mediterranean staples like basil, oregano, and rosemary, to cilantro in Middle Eastern and Indian cuisine, to Thai basil and lemongrass in Southeast Asian cooking. Because flavor and aroma vary widely from herb to herb, there is no single flavor profile common to all of them; a delicate herb like chives and an assertive one like sage play very different roles in a dish.
Fresh herbs are often added toward the end of cooking or used raw as a garnish, since heat can dull their delicate flavor and color. Dried herbs are more concentrated and hold up better to long cooking, so they are more often added early in slow-cooked dishes like stews and braises.
Beyond direct seasoning, herbs are worked into herb butter, herb oil, and herb rub, infused into marinades and herbal infusions, and combined into regional seasoning blends, such as French herbes de Provence or Middle Eastern za'atar.