Déjà vu is a psychological phenomenon that is characterized by a strong feeling of sensation that one has already experienced a current situation, even though it is actually new. The term "déjà vu" comes from French and translates to "already seen." It is a strange feeling in which the places seem to be familiar, although you have visited for the first time.
Scientists have proposed various explanations for déjà vu, but the exact cause is not fully understood. Some theories suggest that déjà vu occurs when there is a mismatch in the brain's processing of incoming sensory information. That is sometimes the information from one of our eyes is received a little late by the brain. So, the information from one eye reaches the brain first and the information from the other eye reaches the brain a little late. So, our brain receives the same information twice. Hence the place you have visited appears familiar.
Déjà vu is a relatively common phenomenon, with surveys indicating that a majority of people have experienced it at least once in their lives. It can lasts only a few seconds, and it typically does not have any lasting consequences or implications.