Insomnia is a common sleep disorder that affects 10 to 15% of the American population. It may be difficulty falling asleep, sleep onset insomnia. It's normal to take five to 20 minutes to fall asleep, but some people take a lot longer. There's also sleep maintenance, insomnia, where people have difficulty staying asleep while it's normal to awaken briefly during the night, it's not normal to be awake for long periods of time, and that can really cut into quality and quantity of sleep. There's also non-restorative sleep awakening in the morning, not feeling rested. Insomnia is common and it's important because it can very much affect the quality of our wake.