A termometre is a device used to measure temperature. It can be found in various forms, such as digital or mercury-based, and is commonly used in homes, laboratories, and hospitals. The readings can help determine if someone has a fever or if a substance is at the right temperature for a specific process. Termometers work by responding to changes in temperature. For example, a mercury thermometer expands and rises in a glass tube as the temperature increases. Digital termometers use electronic sensors to provide quick and accurate readings, making them popular for everyday use.