Why is sleeping important?
Sleep, or at least a period of rest, seems to be observed in all forms of life. If you have had pets such as cats, dogs, or birds, you have no doubt observed that cats and dogs regularly curl up and drop off to sleep and that birds become quiet and go to sleep when darkness comes. Just about all animals, birds, and insects have a need for sleep, or at least periods of reduced activity. For humans, sleep is an absolute must.
Some people think sleep is simply a period of rest. But it is more than that. "Sleep is actually a complicated process of muscles contracting and relaxing, pulse and blood pressure rising and falling and the mind producing its own home movies. When a person falls asleep, all activity decreases and the muscles relax. The heartbeat and breathing rate slow down."
During sleep, changes occur in the body that has an effect on our immune system. Body parts relax and get rest, counteracting the wear and tear of the day's activity. The general clean-up work carried on through the bloodstream operates efficiently, and the chemical balance is restored. So sleep may be compared to a night crew that comes in to get things repaired and cleaned up for the next day.
One of the most important functions of sleep is to allow the nervous system to recuperate from its use during the day.

How Much Sleep Do You Need?
Most adults need seven or eight hours of sleep every night. Some require less, others more. There are some who say that they do reasonably well on four or five hours, though some of them may take naps during the day. Infants and children need more sleep than adults.
When people get older, it happens that they may awaken several times during the night. To some, this is a sign of the onset of serious sleep problems. However, while older people may not have the same quality of sleep that they did when they were younger, experiments have shown that waking up a few times during the night is not a cause for alarm. Usually, the waking time for most who do this is brief, perhaps only a few minutes, before they fall asleep again.
No matter what one's age is, though, one should not expect to have the same soundness of sleep all night.

Dangers From Lack of Sleep
Sleep deprivation cause one lose energy and become quick-tempered. After two days without sleep, a person finds that concetrating for a long duration becomes difficult. Many mistakes are made, especially in routine tasks, and the person's attention slips at times. People who go without sleep for more than three days have great difficulty thinking, seeing, and hearing clearly. Some have periods of hallucinations, during which they see things that do not really exist.
Tests have found that after four days of sleeplessness, a test subject could perform only a few routine tasks. Those tasks requiring attention or even minimum mental agility became unbearable. Loss of concentration and mental agility were not the worst factors. After four and a half days, there were signs of confusion, and the person's visual world became quite disorted.
Lack of sleep can lead to major problems. More than one sleepy person has fallen asleep at the wheel while driving a car and has become involved in a fatal accident. Sleeplessness can also lead to family and marriage problems, since persistent lack of sleep makes one more irritable and harder to get along with. Some people do not realize the importance of getting a good night's sleep.

Getting a Good Night's Sleep
Tips for getting a good night's sleep.

*Sleep in secure, quiet, dark surroundings and on a comfortable bed.
Do not nap late in the day, even if you slept poorly the night before; try to stay awake and to go to bed at your usual time.

*Avoid caffeine before bedtime. Do not use the bed for reading or watching TV.

*Avoid heavy exercise and large meals just before bedtime.

*Maintain regular sleeping hours, as this will help the body acquire a constant sleep-wake rhythm.

*Calm down and relax before you go to bed.

*Avoid doing things that may tend to get you nervous or excited and keep you wider awake. For instance, avoid exciting movies, TV programs, or reading material. Having stimulating discussions just before going to bed may also tend to keep you awake.

Read more atHow To Get A Good Night's Sleep

It is very good to have enough sleep