What are ghosts?

What are ghosts? Our theory is that ghosts are the energy of a person or animals soul that once lived. Ghosts exist in between our dimension and the next, like a radio signal that isn't quite coming in clear on our dimensional frequency. They have not fully crossed over to the spirit realm. There are multiple reasons why ghosts make themselves known to us and how they interact with the living is usually determined by what personality characteristics they had when they where alive.