Matter is a substance that has inertia and occupies physical space. According to modern physics, matter consists of various types of particles, each with mass and size. The most familiar examples of material particles are the electron, the proton and the neutron. Combinations of these particles form atoms.
Simply so, what is something that has mass?
On the Moon, the one-kilogram object would have a weight of 1.6 newtons (0.36 lb). The amount of matter in the object, or its mass, is the same on Earth as it is on the Moon, but the pull of gravity is different. Volume is a measure of the space matter occupies. Matter takes up space.
What is mass simple definition?
A measure of how much matter is in an object. This gold bar is quite small but has a mass of 1 kilogram (about 2.2 pounds), so it contains a lot of matter. Mass is commonly measured by how much something weighs. But weight can change for different locations (such as on the moon) while the mass stays the same.