Mist fans simultaneously blow out air while spraying a fine mist of water droplets. In very hot and dry climates, these water droplets evaporate, but in most cases, the watery mist sinks to a puddle on the ground. Mist fans are mainly for outdoor use, unless you desire your fan giving you a surprise shower inside your living room.
Like mist fans, evaporative air coolers - also known as swamp coolers - employ the physical law of evaporation, except the process takes place internally, within the unit. The air exiting the unit contains water vapor and not water droplets. This makes air coolers suitable for indoor rooms as well as the outdoors.