Although the terms spices, spice seeds, and herbs are often used interchangeably, the differences between them are clearly defined.
Spices are the fragrant or pungent parts of plants grown in tropical and subtropical regions.
Spice seeds are the tiny aromatic fruits and oily seeds of herbaceous plants, including anise, caraway, cumin, fennel, and sesame. In ancient times, spices were used in medicine and to preserve foods. Today, though they may still serve these purposes, they are used primarily as adjuncts in cooking to impart flavor, aroma, or piquancy to foods. In the small quantities used to prepare culinary dishes, spices have little or no nutritive value, but they stimulate the appetite, taste buds, and gastric juices, add zest to food, and delight the gourmet. They have many other uses as well.