47% of people have a nightmare at least once a month.
186
Blue light fends off drowsiness in the middle of the night, which could be useful to people who work at night.
240
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
The harder you concentrate on falling asleep, the less likely you are to fall asleep.
34
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
The average cat sleeps about 2/3 of the day.
203
Bats sleep 18-20 hours per day.
5