Mass is defined as the amount of matter in the object.
Weight is the force the mass has because of the gravity. Daily life, weight and
mass means the same since gravity is almost the same everywhere on earth.
There are many units used for weight measurement. In metric system, basic unit
of weight (mass) is kilogram (kg). Other metric weight units gram, milligram
(mg), microgram (mcg), carat and ton are widely used.
In imperial system, common weight units are pound (lbs), ounce (oz), short
tons, grain, stone (st), hundredweight (cwt).