South Eastern Ghost Research Association

This question has been around for a long, long time.  According to the dictionary this is what a ghost is. 

Ghost-the soul of a dead person, a disembodied spirit imagined as wandering among us or haunting a living person.  A spiritual being.

There are different types of ghostly phenomena that can happen or be caught on film or make pretty good personal experiences.  This is a list of some of them:

Vortex-This usually appears as a long narrow shape, with some solid consistency to it.

Ectoplasm and Mist-This is said to be the residue left behind after a spirit has manifested itself.  Usually this can be seen in pictures as a mist.  If in the case you contact this it is said to feel like a thick spider web that is either extremely cold or hot.  It usually will give you a creepy skin crawling feeling and will make the hair on your body stand up on end.

Apparition-This is best known as a translucent figure that is usually wearing clothes from the era in which they lived.  There have been cases of an apparition appearing like an actual human being, until someone sees it walk through a wall or just disappear into thin air.

Shadow Ghost or Shadow Person-This entity usually appears with as a black mass that really has no fluid shape to it.  Sometimes it looks like a human outline, and at others it would appear like a deep black mass.

Cold Spots-These are thought to appear out of an attempt of a spirit draining the energy around you in order to manifest itself.  The drop in temperature is noticeable by not only touch, but also by thermometers.

Static Charge-This is said to be caused by a spirit brushing up against you.  It can be really creepy when it happens, it will cause extreme cold or hot in the spot of contact.  It will also cause the hair on contact spot to stand up on end.  But the symptoms of a static charge will vary depending on the person.  (There is also a possibility that this is caused by a high EMF Output)

EMF (Electro-Magnetic Frequency)-This can be caused by several different variables.  It can be cause by wiring that is putting out an extremely high Electro-Magnetic Field causing the Gauss Meter to spike. This could also be caused by spirit walking by or touching the device.  *When doing EMF Sweeps also try to trace back the EMF to a singular source or root cause of the spike if non is found then it may be paranormal*

EVP (Electronic Voice Phenomenon)-This is the disembodied voice that is said to be a spirit that imprints itself on audio recording devices during investigations.  This will help tell whether or not the spirit is intelligent.

SSP (Spontaneous Sound Phenomenon)-This occurrence is a type of EVP only instead of voices; there are noises that appear out of nowhere when audio evidence is reviewed. These noises are usually strange and unexplainable.  I have caught several of these, one of wind chimes, one of horse hooves, and one of cabinets opening and shutting on their own.

Fear Cage-This is something that is not a common occurrence.  It is when wires in a building are pushing out an extremely high EMF that forms a square all the way around the room.  This is important to evidence since high EMF can cause paranoia, dizziness, hallucinations, and even cause someone who is sensitive to EMF to hear voices.

Electromagnetic Hyper-Sensitivity-This is the term given to people who are highly sensitive to Electro-Magnetic Fields.  Symptoms of this can vary but here are few of them: Paranoia, Sweating, Sickness, Dizziness, Hearing things that aren't there, Hallucinations, and there are many more.

Matrixing-This effect applies mostly to windows, mirrors.  What this effect does is it can take either scratches, smudges, or an unclean reflective surface to overlap together and possibly create an image that wasn't seen when the picture was taken which makes most people think automatically that is a paranormal occurrence.

Haunted Object-This term refers to an object that honestly could be about anything that for some personal reason a spirit has a strange attraction to so it decides to attach to it.  It may have owned it and it meant a lot to the person prior to death or maybe it was just infatuated with it and wanted to own it. The reason for these objects being subjective to paranormal activity is somewhat uncertain.