On a balancing scale, you can compare objects weight.

If you want to know what the object weighs, you need to use weights for which you know the weight.

Many times we use the concepts weight, mass, and force in everyday conversation and mean the same thing.  In science, there is a difference between these concepts.

Mass is the concept of an object with a certain amount of matter.  It should not be confused with force which can differ depending on differences in gravity.   You have the same mass wherever you are, but your force decreases if you were to stand on the moon which has lower gravity.