most people have some night when day cannot sleep. about one in three american has a problem with sleep. many of these people cannot fall asleep. the name of this problem is insomnia. the word insomnia mean nosleep. some people say, i didn't sleep all night. but that's not really true. they many sleep lightly and wake up several time. in the morning, they only remember the time they were awake, so they think they were awake all night