KG, or kilogram, is a unit of mass in the International System of Units (SI). It is defined as the mass of a specific physical object known as the International Prototype of the Kilogram, which was made of platinum-iridium. One kilogram is equivalent to 1,000 grams and is commonly used to measure weight in various contexts, such as in cooking, science, and everyday life. The kilogram is a fundamental unit in the metric system, which is used worldwide for measurements. It plays a crucial role in various fields, including physics, engineering, and healthcare, where accurate mass measurements are essential for calculations and standards.