The document discusses the water cycle, which is the continuous movement of water on, above, and below the surface of the Earth. It involves five main processes: 1) Evaporation transfers water from surfaces into the atmosphere in vapor form. 2) Transpiration is the process by which plants release water vapor into the air. 3) Condensation occurs when water vapor in the air cools and changes into liquid water droplets. 4) Precipitation deposits water in liquid or solid form back to Earth. 5) Runoff happens when water flows over the land into bodies of water.