Matter includes all physical objects, including stars, books, people, animals, plants, and the oceans. Any physical object that occupies space and has mass is considered matter.
There are three states of matter: solids, liquids, and gases. Some scientists believe that matter comprises other states, such as plasma and Bose-Einstein.
Matter is not limited to only inanimate or living objects. A camera and a dog are both examples of matter because they occupy space and have mass. Matter is also not restricted by size, as both the sun and germs qualify as matter.
Matter also contains the components of anything larger. For example, a beach is considered matter, as are the sand grains that compose it. Matter can include things that can be seen, such as water and sea creatures, as well as those that cannot be seen or heard, such as the many types of gases found in the air, such as oxygen and nitrogen.
Matter can include substances that are neither solid, liquid, nor gas. For example, fire is considered plasma despite being a type of substance.