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Degrees Reaumur

The Réaumur scale is a temperature scale for which the freezing and boiling points of water are defined as 0 and 80 degrees respectively. The scale is named for René Antoine Ferchault de Réaumur. Whilst its use in modern times is rare, it can still be found being used in cheese production measure milk temperature, when making Parmigiano-Reggiano and Gran Padano cheese for example.

Kelvins

The kelvin, symbol K, is the SI base unit of temperature, named after the Belfast-born and University of Glasgow based engineer and physicist William Thomson, 1st Baron Kelvin. The Kelvin scale is an absolute thermodynamic temperature scale, meaning it uses absolute zero as its null point. It is often used to measure the colour temperature of light sources, and is used in photography as a temperature unit to set white balance.