Insomnia is a sleeping disorder that can make it difficult to fall asleep, stay asleep, or both. Many people with insomnia have trouble with either falling asleep or staying asleep. People with insomnia often have other health problems as well. There are different types of insomnia. Insomnia can be acute (short-term) or chronic (long-term). It can also be primary or secondary. Primary insomnia means that sleeplessness is not caused by another condition. Secondary insomnia means that sleeplessness is caused by another condition.