the weight of an object, or of an amount of matter, is typically measured with an instrument such as a spring scale. the scale includes a spring which provides a force to oppose the gravitational force on the object which is being weighed. the gravitational force pulls down, the spring pushes or pulls upwards. typically, the scale has a readout which gives not the weight (which is a force) but rather the mass of the object. spring scales are made with the assumption that they are being used on the surface of the earth. if a spring scale was taken to the moon it would give a misleading reading.