Sleep is a widespread biological phenomenon. Every living organism sleeps at some point. Average time for daily sleep for humans is about 8 hours a day however this time varies from mammal to mammal. Even though we all know what is sleep because we experience it every night there is marked progress is being made in answering three fundamental questions: what is sleep, what are its mechanisms and what are its functions. Sleep is an essential part of our lives. Our bodies collapse with fatigue unless we sleep enough hours every day.
Sleep is necessary for a healthy and balanced life. We need to sleep long enough and well enough to function well during waking hours.
