Okay kiddo, so imagine a house but instead of it being a regular shape like a square or rectangle, it's shaped like a really big curved tunnel. That's what a quonset hut is!
The quonset hut was actually first made during a big war a long time ago. The soldiers needed a quick and easy way to set up shelters/ buildings to keep themselves and their stuff safe, so they came up with this shape. It turned out to be really useful because it was easy to move, assemble, and disassemble when they had to move to new locations.
Nowadays, people still use quonset huts as a way to make quick, affordable buildings. They can be used for all sorts of things like storage for tools, equipment, or vehicles. They can even be turned into a home for people to live in! The curved shape makes them really sturdy and strong, and they can withstand very harsh weather conditions.
So think of a quonset hut as a big, strong, and curved building that's really easy to put up and take down. Pretty cool, huh?