Celsius (°C)
Definition: The degree Celsius (symbol: °C) is a unit of temperature on the Celsius scale. It is named after the Swedish astronomer Anders Celsius, who developed a similar temperature scale in 1742. The Celsius scale is based on the freezing point of water at 0°C and the boiling point of water at 100°C at standard atmospheric pressure.
History/origin: The Celsius scale was originally defined by the freezing and boiling points of water. In 1948, the scale was officially renamed from "centigrade" to "Celsius" by the General Conference on Weights and Measures.
Current use: The Celsius scale is the most widely used temperature scale worldwide, especially in scientific and everyday contexts. It is used in most countries except the United States, which primarily uses Fahrenheit.
Fahrenheit (°F)
Definition: The degree Fahrenheit (symbol: °F) is a unit of temperature on the Fahrenheit scale. It is named after the German physicist Daniel Gabriel Fahrenheit, who proposed the scale in 1724. The Fahrenheit scale is based on the freezing point of water at 32°F and the boiling point of water at 212°F at standard atmospheric pressure.
History/origin: The Fahrenheit scale was developed in the early 18th century. It was widely used in Europe until the 1960s when most countries switched to Celsius. Today, it is primarily used in the United States and its territories.
Current use: The Fahrenheit scale is primarily used in the United States, its territories, and a few other countries for everyday temperature measurements, including weather forecasts and cooking.