Hello all. To fill a concept void, can anyone do a superb explanation if/how one measures mass and the other weight ? -Or not-

Mass is, equivalent to weight, by definition, on the Earth's surface ( 1 g ).
Weight is the force experienced by that mass due to Gravity.

So, while equivalent on the Earth's surface ( 1 g ), your mass on the Moon remains unchanged, but your weight is approx. 1/6 of that on Earth, due to the moon's Gravity being approx. 1/6 that of the Earth.

42 minutes ago, Externet said:

Hello all. To fill a concept void, can anyone do a superb explanation if/how one measures mass and the other weight ? -Or not-

The reading from the one on the left depends on the value of g; it measures weight. The compression of the spring is from a force.

The one on the right does not - any value of g will do. It measures mass. The value of g cancels, since it’s affecting both sides.