Sleep is a necessary and vital biological function of the human and by definition, is "the natural periodic suspension of consciousness during which the powers of the body are restored" according to the first edition of the Merriam-Webster Dictionary. There are two important features of sleep: sleep creates a firm wall between the mind and the outside world and normal sleep is instantly reversible, in other words, any persistent stimulation will always awaken the sleeper (Dement 17). Today, we live in a sleep-deprived society, where nearly 70 million people are affected by sleeping problems and approximately 50% of the adult population is deprived of sleep ("Even Kids" par. 4). Today's environment in general accounts for the lack of sleep among the population. Many people are unaware of the negative consequences that sleep deprivation may have on an individual. It is demanding for everyone to realize the effects insufficient sleep has on their minds and bodies. Sleep is a necessary part of life and sleep deprivation caused by medical and personal reasons may lead to behavioral and health related problems. .
Sleep is essential to a person's physical and emotional well-being. There are two simple theories that are used to describe the need for sleep. First, the restorative quality of sleep enables the rejuvenation and reenergizing of the body and mind. Many researchers believed that during the period of sleep, the brain performs many pivotal housekeeping tasks, such as organizing long-term memory, integrating new information, and repairing and renewing tissues, nerve cells, and other biochemicals. Sleep basically allows the body to drift away from past, present and future activities and feelings and let it rest. Additionally, the adaptive attribute of sleep also accounts for its necessity. Since there is a direct proportion between the amount and quality of sleep achieved to the amount and quality of the next day's productivity, it is vital that one gets sufficient amount of sleep to have a productive next day ("Introduction," sec.