There are four stages of Non-REM sleep. In the first stage, you can be awakened without difficulty but it may leave the person feeling as if he or she has not slept. In the second stage, the body temperature and heart rate drop. At this point, your body gets ready to enter deep sleep. The last two stages are deep sleep stages, with the fourth being more intense. These stages are known as slow-wave, or delta, sleep. If woken up, you may feel disoriented for a while. REM sleep is described as sleep where rapid eye movement occurs. It is also known as “active sleep.” It is during REM sleep that we being to dream. On average a person can have 3 to 5 periods of REM sleep per night. REM sleep is characterized by a number of other features including rapid, low-voltage brain waves, irregular breathing and heart rate, and involuntary muscle movement. Sleep provides the human body with the energy it needs to keep on going. During the state of sleep, the body’s metabolic processes slow down and energy consumption is kept to a minimum. The human body requires rest to sustain its everyday activities, and hence sleep is…