How Does Caffeine in Coffee Makes Us Awake?

How does caffeine keep us awake?

Over 100,000 metric tons of caffeine are consumed around the world every year. That’s equivalent to the weight of 14 Eiffel Towers! Learn more about the science behind the world’s most widely used drug:

Posted by TED-Ed on Monday, July 17, 2017

This explains why coffee makes us awake even though we are very sleepy already.  See the full video.