As with any field of interest, paranormal researchers like to label and categorize hauntings. This can be useful in order to group together similar cases, allowing you to more easily spot trends in findings and reported phenomena.

However, the truth is that we can't categorically identify any supernatural entity and say for certain that it is a ghost, spirit, elemental, poltergeist, demon, or anything else. In fact, after hundreds of years of paranormal research, no one has ever even been able to prove for certain that any supernatural entities exist at all.

What the commonly used terms in the next few lessons actually define is the characteristic of certain types of hauntings, no matter what the paranormal cause of the haunting is. So really, when we use these terms, we're talking about specific types of cases, not any specific type of entity or cause for that case.

These terms refer to instances in...