Fahrenheit is a thermodynamic temperature scale, where the freezing point of water is 32 degrees Fahrenheit (℉) and the boiling point 212℉ (at standard atmospheric pressure). This puts the boiling and freezing points of water exactly 180 degrees apart. Therefore, a degree on the Fahrenheit scale is 1/180 of the interval between the freezing point and the boiling point of water. Absolute zero is defined as -459.67℉.
A temperature difference of 1℉ is the equivalent of a temperature difference 0.556℃.
The Réaumur scale also known as the "octogesimal division", is a temperature scale in which the freezing and boiling points of water are set to 0 and 80 degrees respectively. The scale is named after René Antoine Ferchault de Réaumur, who first proposed something similar in 1730.