What are degrees Rankin used for?

[Azrioch]

My calculator has a conversion table for degrees Rankin and I had no idea what they are used for.

Anyone know?

 

[Phobos]

It's an "absolute temperature" measurement scale in English units.

SAT verbal time...

Kelvin is to Celcius as Rankin is to Fahrenheit

 

[Azrioch]

Thanks.