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 (Rapid Eye Movement), sleep, the movement of eyeballs may occurs and most dream occur in this stage. There are several theories about the cause of occurring dreams. Several says that dreams reveal insight into hidden desires and emotions. If any individual is conscious of appearing in any examinations, then they will see the dream of appearing in exams. If anybody is afraid of any wild animal then the individual may dream as if animals are chasing in their dream.

Most individuals believed that in old days thatvdreams were direct message from deities and ther predicted the future. The Mesopotamians believed that the soul moves our from the human body of sleeping individual, which visits several places and dreamer sees in the sleep. As per Ancient Egyptians, the dream bring messages from God. There are many theories in the regard but it seems unlikely that scenario presented in dreams ever occur in real life.