What do you need to do to make a video go viral? Cats? Jetpacks? A shark attack? A blank screen with no images and no sound? Apparently it’s any and all of these. For those that want to push their view count over six figures, all that’s required is any old video and some cash.

Water-cooler chat used to be dominated by last night's TV, but now people are discussing pop science and the latest Brian Cox viral. Over 450,000 people tune into TED Talks every day, while homemade science videos have millions of views. So how has YouTube made science sexy?

YouTube has grown to become a vast library of content, with all types of video from sports to animals to education. But the sorts of videos that people share varies greatly depending on where they are in the world. YouTube Map Explorer lets you uncover videos from any location.

Gen Z had eluded Subway. Teens are watching less live TV, so they don’t see its ads, and they don't like direct advertising. So Subway launched sitcom The 4 to 9ers, and the first season attracted 18 million viewers. But who wants to watch a TV show created by a fast food chain?