Molecules have different behaviors in different circumstances or surroundings. In heated water, the molecules are flying all over the place. In water at room temp, the molecules are spread apart. In ice, the molecules are scrunched together with no room at all. The type of substance made up of certain molecules like sugar or salt also effects the behavior of the molecules in different circumstances.
All matter comes in one of three forms-solid, liquid, gas.
Crystals can be formed by all three of these. When water freezes, it is a solid, water is already a liquid, and when water evaporates, it becomes a gas. All crystals have a definite shape. For crystals to form, they need time and freedom to grow. Crystal formations form from solutions, the combination of one state of matter into another.