* Annual Precipitation: Deserts receive less than 10 inches (250 millimeters) of precipitation per year. Some extremely arid deserts may receive less than 4 inches (100 millimeters).

* Infrequent Rainfall: The rainfall is not only scarce but also highly irregular and unpredictable. There can be long periods of drought followed by brief, intense downpours.

* Evaporation: Evaporation rates are very high in deserts, exceeding precipitation rates. This means that any water that does fall often evaporates quickly, making it difficult for plants and animals to survive.

Different Types of Deserts:

It's important to remember that there are different types of deserts, and their precipitation can vary:

* Hot and Dry Deserts: These are the most common type of desert, with high temperatures and very low precipitation.

* Cold Deserts: These deserts have cold winters and low precipitation, but can experience warm summers.

* Coastal Deserts: These deserts are located near coastlines and have cooler temperatures and lower precipitation than hot and dry deserts.

In summary: Deserts are characterized by their extremely low precipitation, making them some of the driest environments on Earth.