States of Matter

Matter includes all the material that makes up the universe. It has mass and it takes up space. It includes everything around us: the food we eat, the water we drink, the air we breathe, the ores deep within the earth, as well as the atmosphere above it, the substances that make up the moon, and the stars as well as the dust in the tail of a comet. It is fairly easy to observe that matter exists in different forms or states: solids, liquids, gases, and the less familiar plasma state.