What is the world's largest desert? Hint: it's not hot or covered in sand.

You might remember learning about landforms in science class. From beaches to mountains and archipelagos to dunes, the Earth's surface has many unique environments and terrains.

Among these landscapes are deserts. Images of sand and cacti may come to mind, but did you know there's more than one type of desert?

There are four primary varieties of deserts: hot and dry, semi-arid, coastal and cold, according to National Geographic. The largest desert is much colder than you might expect.

What is the largest desert in the world?

The largest desert in the world is also a continent: Antarctica. It covers approximately 5.5 million square miles, National Geographic reports.

The polar desert also boasts the lowest recorded temperatures on Earth – as low as -128.2 degrees Fahrenheit, according to National Geographic.

The world’s second-largest desert is located on the Earth’s other pole. The Arctic Desert spans around 5.37 million square miles, according to the CIA.

Is the Sahara Desert bigger than the Antarctic Desert?

The Sahara is the third largest desert and the largest hot desert in the world. It extends 3.6 million square miles, according to National Geographic.

Temperatures in the Sahara can reach up to 122 degrees Fahrenheit in the summer.

What is the hottest place on Earth?This is the valley with the highest temperatures.

Contributing: Jacob Livesay

Just Curious for more? We've got you covered

USA TODAY is exploring the questions you and others ask every day. From "What is the highest mountain in the world?" to "How to treat dehydration?" to "What is the biggest state?" – we're striving to find answers to the most common questions you ask every day. Head to our Just Curious section to see what else we can answer.