A ghost is a visual manifestation of a soul, spirit, life force, or life energy. Most people use this term to describe the visual appearance of a human being or creature that has died and passed on to the other side. A ghost is residual in nature -- it does not interact with our physical world.

There are many kinds of phenomenon that fall under the denomination of ghosts but as always with monsters, we have to make a clear distinction between the different categories  and base ourselves on the several following oppositions :

• Human shape / mist and lights
• Ghosts that act autonomously / apparitions that follow the same course of action
• Hallucinations / collectively-observed hauntings

Some ghosts are the exact image of the person they were, others are only recognisable by their faces. Often just a blur of white light is present. Some are said to be solid, some are translucent, others only noticeable by a breath of warm air or a cold hand. A ghost may not appear at all, but be recognised by eerie sounds or moving objects. Other spirits such as poltergeists are said to cause mischief, ranging from spilt milk or tangled yarn to grave accidents, even death.