When it comes to tutorial videos on YouTube, chances are you're using it for one thing - how to tie a tie or a bow-tie.
It's either that or how to take apart a phone or something, but it's pretty mundane stuff. For Kenyan athlete Julius Yego, he used YouTube for something altogether different - winning a gold medal in Beijing at the World Athletic Championships for javelin throwing.
Yego credits rewatching fellow athletes in his field on YouTube repeatedly as his primary coach. "My coach is me, and the YouTube videos... I watched YouTube and it really paid off for me, to see the training techniques and skills they are using."
Kenya is known to produce some of the finest track athletes in the world, but very few javelin throwers. That's why Yego is essentially self-taught in the javelin, along with a bit of help from YouTube and, more recently, a professional coach.
Yego took home the gold medal at Beijing, throwing an impressive 92.72 metres. The world record is held by Czech Republic's Jan Zelezny, who fired a javelin a distance of 98.48 metres.
Here's the throw that won Yego the gold medal.