Sleep is considered a very important part of the daily routine, just like food and water, and about a third of the day is spent sleeping, and in fact the quality of sleep and taking enough sleep at the right times are very important factors for survival, and control is made in Sleep is largely through the body’s internal biological clock, which derives signals from external elements such as sunlight and temperature, and the body’s natural sleep and wake-up cycle is ,
reasonably consistent with the daily regime during a 24-hour period, but most people experience difficulty sleeping or drowning in Deep sleep at some point in their lives, and their lack of adequate sleep leads to an imbalance in the formation and maintenance of pathways that allow learning and the creation of new memories in the brain, where it becomes difficult for people to focus and respond quickly, and it should be noted that sleep affects various tissues and systems The body, showing its effects on the brain, heart, lungs,
metabolism, immune function, disease resistance, and mood. Research indicates that chronic lack of sleep or low-quality sleep increases the risk of some diseases including high blood pressure, cardiovascular disease, diabetes, depression and obesity.   The number of hours of normal sleep varies the number of Normal hours of sleep vary with age, as the body needs in each age group a certain number of hours of sleep, and it should be noted that sleep is affected by factors other than age, such as pregnancy; As the changes that occur to the body at the beginning of pregnancy may increase the need for sleep,
as sleep deprivation for a certain period, and the low quality and frequent interruptions of sleep affect the number of hours of sleep that the body needs,  and here comes an indication of the number of hours needed for each category Age:   Newborns: those between 0 and 3 months need 14-17 hours every day. Infants: Those between 4 and 11 months of age need 12-15 hours of sleep. Young children: Those who
are between one to two years old need 11-14 hours a day. Pre-school: between 3 and 5 years old, they need 10-13 hours a day. School-age children: From 6 to 13 years old, their bodies require 9-11 hours. Adolescents: Who are between 14 to 17 years old, need 8-10 hours a day. Younger adults: between the ages of 18 to 25 years, the length of sleep they need ranges from 7 to 9 hours. Adults: Those between the ages of 26 to 64 years need 7-9 hours. The ,
elderly: those who are over the age of 65 years, the length of sleep they need ranges between 7 to 8 hours. The importance of sleep The following are some of the benefits that an individual reaps when he gets sufficient quantities of sleep:  Maintaining a healthy heart: As the incidence of heart attacks and strokes usually occurs in the morning, which may be caused by the effect of sleep in the vessels It is worth noting that the lack of sleep is linked to the deterioration of blood pressure and cholesterol levels in the body, which are considered risk factors for heart attacks and strokes. In fact, the heart is healthier and safer when the hours of sleep ranges between 7 to 9 hours per day.