Have you ever wondered about this? A desert by definition is a landscape or area that receives very minimal amounts of precipitation.
The actual measurement to be considered a desert is
less than 250 mm per year, or around ten inches, and in fact nearly a third of the
entire Earth’s land surface is considered such!
The largest areas on Earth which fall into this description and category are actually both polar regions. Antarctica has a surface area of 5.5 million square miles, which makes it over two 2 million square
miles larger than the Sahara. In fact, the Sahara is the third largest, behind the
arctic region, which consists of parts of Alaska, Canada, Greenland, Iceland, Norway, Sweden, Finland, and Russia!
Don’t worry, if someone corrects you that the Sahara isn’t the largest desert just
specify that it still is the world’s largest Subtropical, or non-polar, desert!

Source:
http://geology.com/records/largest-desert

ok ,that is good,now what should we do about this information u have given us ?