It is having a feeling of already experienced a situation.The only reasonable explenation would be having experienced it in a previous life.

People experience deja vu, because although they have subconciously done something, been somewhere or had something happen, it wasnt registered at the conscious level.... so when an event occurs, the conscious mind believes its a new experience, whereas the subconcious mind already has experienced it.... *large intake of breath*

Déjà vu (correct spelling) you were close though... The term "déjà vu" (IPA: English /deɪʒɑː vuː/, French /deÊ’a vy/) (French for "already seen", also called paramnesia from the Greek word para (παρα) for parallel and mnÄ“mÄ“ (μνήμη) for memory) describes the experience of feeling that one has witnessed or experienced a new situation previously. The term was coined by a French psychic researcher, Émile Boirac (1851–1917) in his book L'Avenir des sciences psychiques (The Future of Psychic Sciences), which expanded upon an essay he wrote while an undergraduate. The experience of déjà vu is usually accompanied by a compelling sense of familiarity, and also a sense of "eeriness", "strangeness", or "weirdness". The "previous" experience is most frequently attributed to a dream, although in some cases there is a firm sense that the experience "genuinely happened" in the past. Déjà vu has been described as "remembering the future." The experience of déjà vu seems to be very common; in formal studies 70% of people report having experienced it at least once. References to the experience of déjà vu are also found in literature of the past, indicating it is not a new phenomenon. It has been extremely difficult to invoke the déjà vu experience in laboratory settings, therefore making it a subject of few empirical studies. Recently, researchers have found ways to recreate this sensation using hypnosis. In recent years, déjà vu has been subjected to serious psychological and neurophysiological research. The most likely explanation of déjà vu is that it is not an act of "precognition" or "prophecy", but rather an anomaly of memory; it is the impression that an experience is "being recalled". [citation needed] This explanation is substantiated by the fact that the sense of "recollection" at the time is strong in most cases, but that the circumstances of the "previous" experience (when, where and how the earlier experience occurred) are quite uncertain. Likewise, as time passes, subjects can exhibit a strong recollection of having the "unsettling" experience of déjà vu itself, but little to no recollection of the specifics of the event(s) or circumstance(s) they were "remembering" when they had the déjà vu experience. In particular, this may result from an overlap between the neurological systems responsible for short-term memory (events which are perceived as being in the present) and those responsible for long-term memory (events which are perceived as being in the past). In other words, the events would be stored into memory before the conscious part of the brain even receives the information and processes it. This would explain why one is, if it ever comes to mind, powerless trying to twist the outcome of the event in order to create a paradox. The delay is only of a few milliseconds, and besides, already happened at the time the conscious of the individual is experiencing it. Another theory being explored is that of vision. As the theory suggests, one eye may record what is seen fractionally faster than the other, creating that "strong recollection" sensation upon the "same" scene being viewed milliseconds later by the opposite eye. However, this one fails to explain the phenomenon when other sensory inputs are involved, such as the auditive part, and especially the digital part. If one, for instance, experience déjà vu of someone slapping the fingers on his/her left hand, then the déjà vu feeling is certainly not due to his/her right hand to be late on the left one. The global phenomenon must therefore be narrowed down to the brain itself (say, one hemisphere would be late compared to the other one). Considerable strength is added to this interpretation by the fact that computers experience very similar effects when inputs are processed in an unexpected order. This is known as a race condition, and is often responsible for subtle bugs in complex systems. Some believe déjà vu is the memory of dreams. Though the majority of dreams are never remembered, a dreaming person can display activity in the areas of the brain that process long-term memory. It has been speculated that dreams read directly into long-term memory, bypassing short-term memory entirely. In this case, déjà vu might be a memory of a forgotten dream with elements in common with the current waking experience. This may be similar to another phenomenon known as déjà rêvé, or "already dreamed." Not only is the link to dreams as they pertain to déjà vu the subject of scientific and psychological studies, it is also a subject of spiritual texts, as is found in, for example, in the writings of the Bahá'í Faith with quotes like "...perchance when ten years are gone, thou wilt witness in the outer world the very things thou hast dreamed tonight."[12] and "Behold how the thing which thou hast seen in thy dream is, after a considerable lapse of time, fully realized. http://en.wikipedia.org/wiki/Deja_vu

Is this a duplicate question

its like... you open the fridge and turn around.. and suddenly you go...wait... ive been doin the excact moves three times already!

It is usually caused by impressions and images. When you experience this situation, the cerebrum sends you visual senses.

7-23-2017 The brain has filters to identify something important, but they don't always identify why it's important. So deja vu is simply a brain fart.