Déjà vu is a phenomenon where a person feels that they have experienced a situation before, even though it is happening for the first time. This sensation can be brief and often leaves individuals feeling confused or disoriented. It is thought to occur when the brain processes information in a way that creates a false sense of familiarity. Researchers believe that déjà vu may be linked to memory processes in the brain, particularly involving the hippocampus, which plays a key role in forming memories. While the exact cause is still not fully understood, it is a common experience, with studies suggesting that around 60-70% of people have felt it at least once in their lives.