States of Matter at the Macroscopic Level

	Solid - definite, rigid shape and a definite volume, which does not change significantly with change in temperature or pressure. Incompressible.
	Liquid - shape is not rigid, but a definite volume. Liquids flow so their shape is defined by their container. The volume of a liquid will change only slightly with temperature. Incompressible.
	Gas - neither the shape or the volume of a gas are rigid. Gases can expand and contract over large temperatrue ranges. Compressible.