In humans, other mammals, and many other animals that have been studied such as fish, birds, ants, and fruit-flies regular sleep is necessary for survival.

The capability for arousal from sleep is a protective mechanism and also necessary for health and survival. Everyone has a different optimal sleep amount.

Some find that more than 6 hours makes them drowsy and tired, whilst others can't operate properly with less than 8 hours.

The National Sleep Foundation maintains that eight to nine hours of sleep for adult humans is optimal and that sufficient sleep benefits alertness, memory, problem solving and overall health, as well as reducing the risk of accidents.

Insomnia is a sleep disorder characterized by an inability to sleep and/or inability to remain asleep for a reasonable period. It can be caused by fear, stress, anxiety, medications, herbs, caffeine, depression, or bipolar disorder and sometimes occurs for no apparent reason.

The more relaxed a person is, the greater the likelihood of getting a good night's sleep. Aromatherapy oils and massage techniques are now being used increasingly to help with sleep problems as well as relaxation.

Lavender oil undiluted can be placed on a hankerchief by the bed or a few drops put on your temples. Lavender massage oil can be used in the bath or massage liberally onto the skin. Always read the warning before use.