dry-bulb temp. (DB) : the temperature measured using a thermometer with no moisture at its end where it is used to making the measurement.
wet-bulb temp. (WB) : the temperature read using the thermometer having its bulb of thermometer moist.
dew-point temp. (DP) : the temperature at which the air is saturated with water vapor.
Humidity ratio (W) : the proportion of the mass of water per unit mass of dry air.