A weighing scale is a machine for measuring the weight of an object. Most are Spring Scales and others are just balances that are used to standardize display weight, since an object's weight is directly proportional to its mass. They are frequently used to measure the weight of a person, and in many industrial and commercial applications, these are used to decide the weight of things ranging from feathers to overloaded tractor-trailers.
In a typical Spring Scale, the spring stretches or compresses in amount to how hard the Earth pulls down on the object. Every spring will have a proportionality steady that relates how hard you pull it to how far it stretches. It actions force, which is measured in units of force such as pounds-force or Newtons. These scales typically cannot be used for commercial applications unless their springs are temperature remunerated or used at a fairly constant temperature. Spring scales which are lawful for commerce can be calibrated for the precise measurement of mass in the location in which they are used and they can give an precise measurement in kilograms or pounds for this purpose.