According to Freud, the reason why we dream is a 'daytime residue' that spills over into the night. When you are going through something that you can't deal with, when your defences are not adequate enough to deal with the trauma in consciousness, that is when your subconscious mind tries to play it out.This is mentioned in the article link. For exmple people who commit wrong things will be haunted by such nightmares.

 Of course the the other things you mentioned like dreams of such kind take place in those people who are in bad health.

I have tons of problems on my mind but I have not experienced any nightmare ever apart from an occasional dream of falling while sleeping And the sudden falling sensation wakes me up which sometimes looks so real even after woken up.  

That's because you are hale and healthy. If one is hale and healthy and happy with their lives and laughing as part of their lives, such nightmares may not take place. I too do not dream nightmares . If fallen asleep, i sleep a sound sleep without dreams. What to speak of nightmares.

very less nightmares i have been encountered with but only some of them effected me because many of them i forget when i wake up

bhuyali saroj wrote:

very less nightmares i have been encountered with but only some of them effected me because many of them i forget when i wake up

@ Anil..

I am agree with Usha ji nightmares are dreams both are psychological and physical. I have nightmares which unrest me. I have problem of sleeplessness. What I dream and nightmares most of them, I remember all these when I wake up.

Most people are never able to recollect their dreams or nightmares , the more you focus and try to recollect, the farther it seems to go. Many studies have been conducted on this subject and the best advise given was to keep a paper and pen handy and write down everything you remember as soon as you wake up without trying to focus, so that at least some bits are remembered.This was done for study purpose and was apparently helpful.

I had nightmares during my childhood. I often saw dead body processions in sleep. For this reason only, my parents changed the house. Now I often see myself in awkward position in dream viz. without any clothing among guests. I also dream that I am falling from some high places or from stairs.  But now I am not so scared. all is well. 

Gulshan Kumar Ajmani wrote:

I had nightmares during my childhood. I often saw dead body processions in sleep. For this reason only, my parents changed the house. Now I often see myself in awkward position in dream viz. without any clothing among guests. I also dream that I am falling from some high places or from stairs.  But now I am not so scared. all is well. 

Yes sir. these are all common night mares like being chased by a snake, missing the train and falling from a high mountain. These fears which we think in the conscious condition. And these fears go in to our subconscious. They surface up some day or other.

Good to know now you do not have such night mares.

 

rambabu wrote:

Night mares are certainly disruptive. You wake up from your sleep with a jolt. This generally happens as said in the link article due to unfulfilled desires which are suppressed by force. But these desires live in your subconscious and come out causing havoc . When you are extremely weak owing to an ailment or hungry, such nightmares occur,.

 Person who is done enough Physical labor never have dreams and nightmares. Vo Ghodey bechkar sota hai.

anil wrote:

rambabu wrote:

Night mares are certainly disruptive. You wake up from your sleep with a jolt. This generally happens as said in the link article due to unfulfilled desires which are suppressed by force. But these desires live in your subconscious and come out causing havoc . When you are extremely weak owing to an ailment or hungry, such nightmares occur,.

 Person who is done enough Physical labor never have dreams and nightmares. Vo Ghodey bechkar sota hai.

True. A healthy person will not be affected by night mares.  Those who are unhealthy dream night mares. I enjoy night after night a sound and dreamless sleep.

 

A person has to actually worry when he has dreamless sleep because it is part of a healthy sleep cycle  or else it is because he or she is simply unable to recollect it because it is very essential for us to dream and most healthy people have dreams at night , nightmares are rare and occur only when there is mental disturbance of some kind or post traumatic stress disorder which can be the reason.

http://www.pwpotential.org/importance-dreams