Insomnia may include the following:
- Difficulty falling asleep
- Difficulty remaining asleep or waking up many times during the night (not necessarily having any difficulty falling asleep)
- Waking up too early in the morning
- Not feeling refreshed after a night's sleep
In all of these instances the person experiences daytime fatigue and feels as if he or she did not have enough sleep. Poor sleep for any length of time can lead to mood disturbances, lack of motivation, decreased attention span, trouble with concentration, low levels of energy, increased fatigue, and increased risk of accidents. Approximately three-fifths of the average person's life is spent sleeping. Healthy sleep is vital to the human body and important for the optimal functioning of the brain, immune system, and other organs.
Types of Insomnia
There are three types of insomnia:
- Transient insomnia - sleep difficulties that last for a few days; there is little or no evidence of impairment of functioning during the day.
- Moderate insomnia - sleep difficulties that last for less than a month, that mildly affect functioning during the day, together with feelings of irritability and fatigue
- Chronic insomnia - sleep difficulties that last for more than a month, that severely impair functioning during the day, and cause strong feelings of restlessness, irritability, anxiety, and fatigue.
Advanced age (over 60) makes individuals more likely to experience insomnia.
Treatment for insomnia focuses on the reason why you don't sleep well. If you have a medical problem, such as chronic pain, or an emotional problem, such as stress, treating that problem may help you sleep better. 
Regular exercise also helps. Techniques such as relaxation exercises, sleep restriction therapy, and reconditioning may be useful.