Units of mass are standard measurements used to quantify the amount of matter in an object. The most common unit of mass in the metric system is the kilogram, while in the imperial system, the pound is widely used. Other units include the gram and ton, which serve specific purposes in various contexts. Mass is different from weight, which measures the force of gravity on an object. For example, an object with a mass of 1 kilogram weighs approximately 2.2 pounds on Earth. Understanding these units helps in fields like science, cooking, and engineering, where precise measurements are essential.