Bats sleep 18-20 hours per day.
5
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
You forget 90% of your dreams.
256
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
The strangers in your dreams are actually people that you've seen in real life.
50