Solids, liquids, and gases are the three states of matter commonly found on earth.

A solid is rigid and possesses a definite shape.

A liquid flows and takes the shape of its container, except that it forms a flat or slightly curved upper surface when acted upon by gravity. (In zero gravity, liquids assume a spherical shape.) Both liquid and solid samples have volumes that are very nearly independent of pressure.

A gas takes both the shape and volume of its container.