We are all familiar with the dreams. We see various type of dreams everyday. Some are pleasant and refreshing. some terrify us so much that we cry out in sleep.Some leave us totally perplexed.Many questions arise in our mind regarding dreams, about their nature, causes and utility.
                                I remember some incident in our crazy childhood, i shouldn't tell the name of my childhood friend. But i can say that our childhood friend circle know this incident and remember the name also. I'm sorry for this cheap story. Dream has the cause and the purpose, as i remember after singing whole night and day in Tihar festival, during third night one friend was singing in Dream. It is clear and loud tone ,we where confused at first. Some people have habit of talking in dreams, Walking in Dreams and some are kicking in Dreams( some may be crazy Drama, (unknown). 
                               The visual experiences that a person has during sleep are termed as dreams. Dreams are seen in images and there is a continuity in the various images that are seen. That is one image leads to the other,somewhat as in a movie. As a rule dreams are seen more often when a person is not in deep sleep, the optimum period being a few hours before waking . This is why people see more dreams in the last phase of the night. Nightmares are seen more often than pleasant dreams. Very often our dreams seem so real that we mistake them for actual happenings.
                              The material of most dreams is drawn from the past experiences of the person. Those incidents which have occurred in the recent past and which have affected us strongly are re-enacted in our dreams.There was a student who used to dream every night that he was going to the station, but he missed the train. A psychiatrist who was consulted explained that this was because the student had sat for a very difficult examination several times but had always been unsuccessful. This had greatly upset him and had triggered off the dreams.
                                                                                     Very often two or more people experience similar dreams at the same time. This happens when the people concerned have been subjected to experiences of the same kind. For example, if there has been a death of a much Loved person in the family members could dream about the dead relative at the same time. Similarly, victims of natural calamities like floods or famines and war refugees who have gone through the same horrifying experiences very often dream alike. The external stimulation that affect a person who is sleeping exert a strong influence on his dreams. It has been observed during experiments that if water is sprinkled on a sleeping person without waking him,he sees dreams of being drenched in rain. Similarly , if you prick a sleeping person, he goes and dreams of sword fight ,battles ,operations and such things. It has been our common experience that when we are hungry or thirsty in sleep, we dream of costly feasts or of drinking very large quantities of water.
                       Another cause of dreams is the unsolved problems of the day. Those problems that keep us occupied during most of the day induce dreams related to them. In these dreams we try to solve these problems. Surprisingly, very often we find their solutions in our dream, like Neil Bohr's discovered the atomic structure in dreams. If we go to sleep after reading an absorbing book , we are very likely to dream about it. Unfulfilled desires and necessities also induce dreams. The child who has been forbidden to eat chocolates makes up for it by dreaming about eating them. Like most things in life dreams too have their purpose . Dreams help people in maintaining his mental stability . In the body numerous physiological and mental changes keep occurring. These create a lot of mental strain and maintain optimum mental equilibrium. Through dreams a person fulfill his suppressed desires, which he cannot fulfill in real life. Another utility of dreams is that they help in the diagnosis and treatment of mental illnesses.