In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
The record for the longest scientifically documented period without sleep is 264.4 hours (eleven days).
15
You forget 90% of your dreams.
256
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
Cows can sleep standing up, but they can only dream lying down.
745
If you hold farts in during the day, they'll just come out when you sleep.
16
Sleeping on your stomach can induce weirder, scarier, and sexier dreams.
22
47% of people have a nightmare at least once a month.
186