All deserts are hot

I thought deserts were just a large area of land covered with sand. But, in Grade 7, I learnt that deserts are areas of extreme temperature. I believe many people think that deserts are just very big sandy areas, like the Sahara Desert and the Thar Desert, but don't now that there is something called a 'cold desert' that also exists.

Deserts are not defined by their temperatures, but by their lack of precipitation. And while most of the world's most famous deserts are indeed hot, there are some deserts that also experience brutal cold. Known as polar deserts, these arid areas can be found in Iran (called Dasht-e Lut) and Northern Greenland, for example.