The process by which liquid water becomes water vapor is known as evaporation. This physical change occurs when water molecules gain enough energy, typically from heat, to overcome the intermolecular forces holding them in a liquid state. Factors affecting evaporation include temperature, surface area, and humidity; higher temperatures and larger surface areas increase the rate of evaporation. This process is vital in the water cycle, contributing to atmospheric moisture and influencing weather patterns. Additionally, evaporation plays a key role in cooling mechanisms, such as sweating, which helps regulate body temperature.