Water on the on surface of Earth is constantly changing between these three states. Ice can change to become water or water vapor. Water can change to become ice or water vapor.
Water vapor can change to become ice or water.
These continuous changes in state create a cycle of repeating events. Water continually circulates between the surface of Earth and its atmosphere in what is called the hydrologic or water cycle. Responding to heat energy from the Sun, water in oceans, lakes, swamps, rivers, plants and even in your body can turn into water vapor. Water vapor in the atmosphere condenses as it cools to form clouds. Once the droplets of condensed water vapor are too heavy to remain in the atmosphere, they fall to Earth as precipitation.