Three different types of ghost hauntings
Residual Haunting:
A residual haunting is easy to classify in that the entity does not interact with the living. The events surrounding the spirit appear to be played back as though they are part of a recording.
Repetition is the key here because the events are usually on a set schedule, or a key thing will trigger the event. The entity won't notice you and will not interact with you.
Intelligent Haunting:
The Intelligent Haunting involves an entity which interacts with its environment and shows signs of logic or understanding. They may include full body apparitions, or
may simply show small signs such as a pen moving, a phone ringing, or the scent of roses. Intelligent Hauntings are usually
the result of a human who has passed. The spirit may be earth-bound, meaning they remain on earth, or they may be non-earth-bound, meaning that they have passed to
another realm.
Non-Human Haunting:
These are beings which are not human, and may be more aggressive in their activities than a human spirit. Sometimes referred to as Demons, it is important to keep your distance
from these beings. Do not Fear them, but do respect them as you would a wild animal.
New comers to the ghost investigation field unknowingly cause problems in these cases by using "Talking Boards" or dark magic.