Majority of the persons in the world dream at the night while sleeping. The basic theory is that the dreaming by an individual is dependent on the conditions and situations that people face in their life. If the person is thinking positive and dream for becoming a successful person so the dream is also positive. A unexpected dreaming by the person who watches horror films and dream is also horror.
An average person may have three to five dreams per night, however, most dreams are quickly forgotten. Dreams mainly occur in the Rapid Eye Movement (REM) stage of sleep. At that stage the activity of the brain is high and feeling comes as if we are awake. If one awakens during the REM phase of sleep, it is likely that dream is remembered, otherwise dreams are immediately forgotten. During REM sleep, the movement of eyeballs occur and most dreams occur in this stage.
There are many theories about cause of occurring dreams. Some say the dreams reveal insight into hidden desires and emotions. If somebody is conscious of appearing in exams, he/she will see dream of appearing in exams. If someone is afraid of any wild animal, the person may dream as if the animals is chasing.
In olden days people believed that dreams were direct message from deities and they predicted the future. The Mesopotamians believed that the soul moves out from the body of sleeping person which visits the places and persons the dreamer sees in the sleep. According to ancient Egyptians, the dreams bring messages from God. There are several theories in this regard but it seems unlikely that scenario presented in dreams ever occur in real life.
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