Dr.Patricia A. Farrell, a well-known author/psychologist has written this book on sleep for all those who wish they could get a restful night's sleep. Included in the updated and revised book is the latest information on why we must sleep, how our immune system is affected, how long we need to sleep, whether or not naps are helpful, what happens while we sleep (very exciting), the medical disorders that are associated with lack of sleep, how to use "sleep hygiene" to advantage and to avoid "sleep debt," why TVs, computers and tablets interfere with our sleep. You'll find out how to take a test online to get a "sleepiness" score, where you can find sleep specialists, how to find a sleep center and ways to best manage sleep. Is the brain active while you sleep or does it just manufacture dreams? Could you actually die if you didn't sleep? Why are corporations allowing their employees to sleep on the job? If you want more information on the research, there's a useful References section to guide you to the important sources. A life stress scale as well as a link to decide if you're a "lark" or an "owl" in terms of sleep.