|It's fun to pretend|
|Fails from the crypt|
“” The paranormal can best be thought of as a subset of pseudoscience. What sets the paranormal apart from other pseudosciences is a reliance on explanations for alleged phenomena that are well outside the bounds of established science. Thus, paranormal phenomena include extrasensory perception (ESP), telekinesis, ghosts, poltergeists, life after death, reincarnation, faith healing, human auras, and so forth. The explanations for these allied phenomena are phrased in vague terms of "psychic forces", "human energy fields", and so on. This is in contrast to many pseudoscientific explanations for other nonparanormal phenomena, which, although very bad science, are still couched in acceptable scientific terms.
|—Terence Hines, Pseudoscience and the Paranormal (2003)|
Paranormal activity is a catch-all phrase for anything supernatural or supposedly "unexplained". By "unexplained" this usually means that it lacks a supposedly scientific explanation — or more likely, the scientific explanation of people being hysterical isn't as fun, dramatic or interesting as real ghosts and spirits. That is why all paranormal woo-meisters do not (and cannot) base their arguments on empirical evidence but rather on anecdote, testimony, and suspicion. The paranormal is a subset of pseudoscience.
More often than not, paranormal activities invoke supernatural rather than naturalistic explanations — although a few sub-fields of paranormal investigation such as cryptozoology do claim "naturalistic" explanations, but these are mostly bullshit.
Bullshit or not, a large percentage of the population apparently believes in some level of paranormal activities, at least according to 2006 Baylor Religion Survey. Of course, how that relates to the belief in religion in general is debated.
In general, paranormal phenomena are outside of what one would normally expect to observe in the real world. Furthermore, the phenomena are generally not reproducible under controlled conditions and it is therefore not possible to investigate them using the scientific method. For these deep-seated reasons (among several others of equal hinderance to the "believers") paranormal phenomena are per definition classed as pseudoscience.
However, many of the legitimate scientific investigations that have been made into paranormal activity have turned up interesting results, although most, if not all, turn out to have naturalistic explanations. Ghosts, for instance, can be explained by minor hallucinations that have been replicated in labs. The 'spooky' or 'sickly' feeling of walking into a haunted house has been replicated by using very low frequency soundwaves. Acts such as fortune telling or talking to the dead can easily be replicated in controlled conditions by people, such as Derren Brown, utilising the techniques that mediums and fortune-tellers are suspected of using to dupe otherwise innocent customers (e.g., cold reading or hot reading).