The technological device used to measure temperature is a thermometer. Thermometers come in various types, including digital, analog, infrared, and bimetallic, each suited for different applications such as clinical, environmental, or industrial uses. Digital thermometers provide quick and accurate readings and are commonly used in medical settings. A traditional mercury thermometer relies on the expansion of mercury to indicate temperature changes. Infrared thermometers allow for non-contact temperature measurement, useful in situations where contact is impractical. The accurate measurement of temperature is vital in fields ranging from medicine to weather forecasting.