"What Does the Fox Say?" is a YouTube hit. It's from a Norwegian pair of brothers known together as Ylvis. If you're wondering what foxes really sound like, we've got that video too.

Fox costumes are on the rise this year thanks to a Norweigan duo's YouTube video gone viral: "The Fox (What Does the Fox Say?)." ...

It has also garnered hundreds of amused comments - several of them from people relieved to finally find the answer to "What does the fox say".

Parents and kids are going to have an absolute blast reading What Does the Fox Say? out loud.” “What Does the Fox Say?” will be available in bookstores Dec. 10.

What does the fox say? If you’ve been vaguely online in the past five years, you probably know the answer in the form of a catchy, annoying, beloved refrain.

YouTube's top 10 most viewed video lists for 2013, led by Norwegian comedy duo Ylvis' pop hit "The Fox", both around the world and in Australia.