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
Studies show that the colder the room you sleep in, the more likely you are to have a bad dream.
28
The average cat sleeps about 2/3 of the day.
203
47% of people have a nightmare at least once a month.
186
In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
13
"Dysania" is the state of finding it hard getting up out of bed in the morning.
33