What is matter?

In simple terms matter is anything that takes up space - this does not necessarily mean you can see it of course. Matter is anything that has a mass so this includes gases which of course cannot normally be seen - the air around us is matter, the water we drink is matter, we are matter. The universe is basically made up of matter and energy. Put really simply, matter is stuff and energy is what moves stuff. Matter can be broken down into 3 different states, solid, liquid and gas (there are more but these are the basic 3).

Matter can change from one state to another for example when heat is applied (ice is a good example - it starts as a solid, apply heat and it turns to liquid (water), apply yet more heat and it turns to gas - steam) - so in this case the heat is the energy.

So basically matter is what makes up all substances. Molecules, atoms and sub-atomic particles are all matter. The major properties of matter is that it takes up space, has a mass and attracts other matter with gravity.