It is commonly believed that everybody should get at least eight hours of sleep a day. But a lot of people try to get by on less, thinking that sleeping is just a waste of their time. Even some experts claim that it is the quality of sleep that counts rather than the quantity, and that we could live healthy lives with only three or four hours of good sleep. To them, "good sleep" is characterized by REM (Rapid-Eye Movement). It is during this phase of sleep that we dream.
Dreams and their interpretation are other interesting phenomena associated with sleeping. Throughout history, seers have tried to use them as a guide to the future. Today, psychologists are apt to see them as the acting out of the anxieties and fantasies we cannot express during our waking hours. For Sigmund Freud, they were symbolic expressions of our sexual desires.
