I want to know did everyone ever have deja vu?sometimes i were dream then may happen in the real life,what kind of dream make you impressed?
yes sometimes i feel deja vu
It happened to me 2-3 times when I was young. Sometime when I awared this event was deja vu I tried to acted differently.
Science explained because it is brain mistake.
In paranormal term it happen because you travel through time to future when you dream.
Like Berat said, apparently it's a memory failure. I suppose it could be explained because we have many similar experiences throughout the day. There may be times when a number of experiences occur at the same time which may not be significant on their own, but when combined trigger a feeling that some people think of as a deja vu.
If you are a bit more into supernatural stuff or subscribe to a different understanding of time or whatever you might look for alternative explanations. Personally I like, but do not believe in, the idea that time as we know it is just a concept and not an actual thing of its own. What I mean is that we're like an animation that keeps looping and everthing is already done, it's just that after the loop is done our memory is reset and we then live the entire thing again, over and over. Some moments though, there's a memory failure where we suddenly get a glimpse of our memory already having looped through this part once. This would be the "deja vu". Then again, this would be deterministic and not all people like this idea because they prefer free will. But what if it's both deterministic and with a bit of free will. Once you realize it's a loop you're free to alter the rest of the loop and change it for the better. Just think of it as improving the loop, and make it as beautiful as possible. Then you can enjoy a beautiful loop forever.
Actually it's not real, you didn't experience same condition in the past, never, it's the first time you experience with this condition in real, its just a one of the failure of our memories. Our Brains don't always work perfectly.
We can't say it is a disease or memory problem because it's very normal condition for every people even healthy one. It's just short-timed mistake.
Seeing something you saw in a dream is called "Reve vu" :)