Mass : measures the amount of MATTER a substance is made up of
Weight : measures the PULL OF GRAVITY on a substance
How are mass and weight different ? Mass is a measurement of the amount of matter in a substance, while weight is a measure of gravity's effect on that mass.
How does mass affect weight ? As your body grows, you will have more mass, which also means you will weigh more. That’s because when you’re on the earth, the amount of gravity that pulls on you stays the same.
So when your mass changes, so does your weight!
Hope this helps :)