There are three states of matter: Solid, liquid and gas.
Solids have a definite shape and a definite volume. They have a tendency to maintain their shape even when an external force is applied. Examples: wood, plastic
Liquids have a definite volume, but no definite shape. They take the shape of the container. Examples: water, oil
Gases neither have a definite volume nor a definite shape. Example: oxygen, carbon dioxide