People usually confuse precognition with deja vu as they seem to be same. However, there is a prominent difference between them. Precognition (from the Latin prae-, “before” and cognitio, “acquiring knowledge”), is defined as a foreknowledge of an event, especially as a form of extrasensory perception. Deja vu, on the other hand, is a French word which literally means, “already seen”. An overwhelming sense of familiarity with something that shouldn’t be familiar at all.
It is very much clear that these two terms are different from each other as one is the foreknowledge and the other is the familiarity with the event. Precognition does not employ the basic senses of a human being but a more psychological one, that’s why it is defined as extrasensory perception.
Like telepathy, in which a person transfers its thought to another person’s mind without using the usual senses, is also an extrasensory perception (ESP). Precognition has a tradition of foreseeing the future through dreams or by some other devices or techniques for example; by reading the direction of the wind, by some action taking place involving birds or animals. They also employ a deck of cards which is still very much practiced, and by throwing the dices.
Deja vu can be hard to detect. A person may have familiarity with something or someplace, which is very common among people. They might recall an event or a place which they have lived in the past. It might be a memory from your childhood, that you face after a long period of years and may feel that it has happened before or you have seen this before. Sometimes you might come across a person that seems deeply familiar.