What is the Milk Crate Challenge, how did it explode out of nowhere and why are people doing it?

You’ll be forgiven if you don’t instantly know what the Milk Crate Challenge is or why it’s a thing. 

The trend started in the US and has been sweeping across social media in recent days, particularly on TikTok, Twitter and Instagram. 

OK so what is it?

Basically, users have been posting videos…