Degrees Celsius (°C) is a unit of temperature measurement used in most countries around the world. It is part of the metric system and is based on the freezing and boiling points of water. Specifically, water freezes at 0 °C and boils at 100 °C under standard atmospheric conditions. This scale is widely used in scientific contexts and everyday life, such as weather reports and cooking. The Celsius scale was developed by the Swedish astronomer Anders Celsius in the 18th century. It is commonly used in contrast to the Fahrenheit scale, which is primarily used in the United States. The Celsius scale is favored for its simplicity and direct relation to the properties of water, making it intuitive for many applications.