Insomnia is caused by medical conditions, emotional disorders like anxiety and depression, hormonal changes during aging, and behavioral factors like irregular sleep schedules. Problems from lack of sleep include increased stress, poor coordination, decreased work performance, and increased risk of accidents. There are things people can do to improve sleep, such as exercising during the day, avoiding stimulants like caffeine before bed, developing a relaxing bedtime routine, and making sure the bedroom is quiet and comfortable. Maintaining good sleep hygiene can help treat insomnia.