Your body, your house, your dog, the Earth: all these things are made of matter. Matter is the name that scientists give to all of the substances in the universe.
Is water a kind of matter? Yes, water is a kind of matter called a liquid. Other kinds of liquid include milk and the gasoline we pump into our cars. Water is by far the most common form of liquid on Earth, though — most of the Earth’s surface is covered by water.
Wave your hand through the air. You can feel the air wooshing past your hand. Is the air made of matter? Yes, air is a kind of matter called a gas. Other kinds of gasses include carbon dioxide (which plants breathe) and helium (which is used to make toy balloons float).
Most of the things you can see or touch are made of matter. Even things you can’t see (like the air) are made of matter. Are there things in this world that aren’t made of matter? Yes: some things are made of energy, which is different than matter. There are lots of ways to see energy in the world. Sunlight is a kind of energy. When a bolt of lightning hits the Earth during a storm, that’s energy too.