Maybe it can be likened to hallucination when you see things that are unreal but it is all about spirits. Not really a ghost but let's say you see a person with a familiar face going to the crowd and suddenly it is gone. That happened to me not once but several times. When I consulted a seer she said that a spirit is sending me a message. Unfortunately the message is not defined so it is like until now I am still waiting for the next appearance of that face.