A kilogram is a unit of mass in the metric system, symbolized as kg. It is defined as the mass of a specific platinum-iridium cylinder kept at the International Bureau of Weights and Measures. One kilogram is equivalent to 1,000 grams, making it a standard measurement for everyday items like food and household goods. Kilograms are commonly used around the world for measuring weight, especially in countries that follow the metric system. For example, a person's weight might be expressed in kilograms, such as 70 kg for someone who weighs 154 pounds. This unit helps provide a clear and consistent way to quantify mass.