Did you know liquid is matter? Actually, matter is all around us. Matter is anything that takes up space and has mass (or weight). There are three types of matter commonly found on Earth. A liquid is one type. A liquid does not have its own shape. It takes the shape of its container. It flows easily.
Milk is a liquid. In a carton, milk takes the shape of the carton. In a cup, milk takes the shape of the cup. When spilled on the floor it takes a new shape-- the shape of a puddle!