Humidity measurement is crucial because it affects everything from human comfort to the likelihood of rain. There are various types of hygrometers; the “psychrometer” uses two thermometers (one wet, one dry) to calculate humidity through evaporation. Modern electronic hygrometers use changes in electrical capacitance or resistance to provide digital readings. High humidity readings suggest that the air is nearly saturated, which can lead to dew, fog or cloud formation. Conversely, low humidity indicates dry air, which promotes evaporation. Monitoring these levels helps meteorologists predict precipitation and helps industries maintain the specific environmental conditions required for manufacturing.