the importance of sleep

During sleep, the brain repairs itself and stores information. If we do not sleep, then we become tired and cannot think properly. So, we will have poor immune system. People sleep badly when they are not relaxed. They are thinking about their work or studies. Late at night, they have a phone call and look at email. Moreover, they take a drink which contain caffeine and have a dinner just before sleep. To sleep well, we need a comfortable bed besides a quiet and dark room. Furthermore, we must do daily routine every evening before sleep. Lastly, try to go to sleep at the same time every day.