This glossary of terms* is very important to have and understand when dealing with the paranormal

APPARITION A disembodied spirit visible to human beings.
ASTRAL PLANE A level of existence separate from, and in some sense higher than, the phsyical world, according to certain philosophies and religious teachings.
COLD SPOT A place that is cooler than the surrounding area. It is thought by some to be an indication of a supernatural presence drawing energy from its environment in order to manifest.
DIGITAL INFRARED CAMERA A device used to capture images invisible to the human eye at the "hot" end of the light spectrum. It is capable of feeding information to a computer, where its infrared images may be stored on a hard drive.
DIGITAL THERMOMETER A device used to record the presence of cold spots and hot spots, sometimes during an apparent paranormal event. Some digital thermometers record temperatures second-by-second for PC storage and graphical charting.
ELECTROMAGNETIC FIELD RECORDER A device used to record data on elctromagnetic fields (EMFs). Its use is controversial among ghost hunters in that EMFs from power lines, television sets, kitchen appliances, etc. srround us constantly, as well as the fact that it has yet to be categorically proven that ghosts emit EM energy. On the other hand, some researchers say ghosts disrupt EMFs.
EVP Electronic voice phenomena. Audio devices may record disembodied voices and other supernatural sounds that are inaudible to the human ear without mechanical intervention.
FLOATING ORB A spherical image, usually a translucent white though sometimes a reddish or bluish hue, which inexplicably registers on film or videotape. Its presence is thought by some to be an indicator of supernatural activity.
GHOST The soul or spirit of a dead person, reflecting the apperance of his or her living body but less substantial. Ghosts may exist in a state of semi-awareness or be completely cognizant of their living observers.
GHOST HUNTER / INVESTIGATOR A person who attempts to gather evidence of ghosts or other paranormal activity. This may be accomplished by means of still photography, video, audio, EMF recordings, EVP recordings, or other media.
HAUNTING The manifestation of a ghostly presence attached to a specific person or location.
INHUMAN ENTITY A demon or other spirit intent on causing harm to living beings. Also known as a negative entity.
INTELLIGENT HAUNTING A supernatural entity that is aware of its surroundings and / or observers and is capable of interaction with them.
MATERIALIZATION The procedure through which a ghost appears. Materialization can be sudden or gradual, resulting in an entity that is indistinct or seemingly quite solid.
MATRIXING The natural tendency of the human mind to add details to sensory input (perceived through the visual, auditory, olfactory, or tactile senses) so as to create a familiar or easily understood pattern. In effect, matrixing is mentallly "filling in the blanks."
OUIJA BOARD A wooden board preprinted with letters, numbers, and words used by mediums to receive supernatural communications.
PARANORMAL The realm of occurrences and phenomena removed from those to which people are exposed in everyday experience.
PHANTOM SMELL Any scent through which a supernatural entity is attempting to express itself. Typically, phantom smells are reminiscent of flowers, cigarettes, or perfume, but they don't come from any identifiable source.
POLTERGEIST A ghost that manifests its presence through noises, rappings, the moving of objects, and the creation of disorder. The relocation of furniture is an indication of poltergeist activity.
RESIDUAL HAUNTING A scene from the past that continues to be played out over and overa gain, like a recording, with the witness of the phenomenon essentally peering into a former era. The ghostly participants in these time displacements often seem unaware of their living observers.
SENSITIVE A medium or clairvoyant. A sensitive can see or feel people, objects, and events in the realm of the paranormal.
THERMAL-IMAGING DIGITAL CAMERA A device that records images of long-wavelength infrared radiation (i.e., heat) that are invisible to the human eye. The thermal-imaging camera facilitates the capture of images in darkness, smoke, or fog.
VORTEX An anomaly that sometimes shows up in still photographs taken at the site of a suspected haunting, appearing as a translucent white tube or funnel-shaped mass. Some researchers believe vortices may be portals to the spirit realm.

*This list was compiled by Jason Hawes and Grant Wilson in their book, Ghost Hunting. ©2007. Pocket Books, New York, NY.