A dozen is a unit of measurement equal to 12 items, widely used to quantify goods, objects, or units of various types. It measures the number of individual items within a set, providing a standardized and convenient way to express quantities. The symbol for dozen is "dz." While not part of the International System of Units (SI), the dozen is commonly used in everyday commerce and cooking, particularly for items like eggs, baked goods, and small manufactured products. Its importance lies in its practical application, simplifying transactions and communications by providing a clear, easily understood quantity. In scientific contexts, although less common, the dozen can still be useful for specific measurements, particularly where items are packaged or sold in sets of twelve, highlighting its enduring utility across both practical and specialized fields.