There are two types of people in the world: those who wake up with a smile on their faces, and those who are super grumpy till they have their morning coffee. If you're the second kind, then this video by AsapSCIENCE will surely interest you.

If you think coffee helps you 'wake up fully,' you're wrong. Caffeine is ineffective in the early morning hours and will only make you resistant to it. Here's the scientific explanation: