What is a Celsius thermometer?

A Celsius thermometer is a device used to measure temperature, utilizing the Celsius scale where water freezes at 0 degrees and boils at 100 degrees under standard atmospheric conditions. It typically contains a liquid, such as Mercury or colored alcohol, that expands or contracts in response to temperature changes, allowing for accurate readings. The scale is widely used in scientific, educational, and everyday contexts due to its straightforward relation to the physical properties of water.