A ghost — or spirit or apparition — is the energy, soul or personality of a person who has died and has somehow gotten stuck between this plane of existence and the next. Most researchers believe that these spirits do not know they are dead. Very often they have died under traumatic, unusual or highly emotional circumstances.
Ghosts can be perceived by the living in a number of ways: through sight (apparitions), sound (voices), smell (fragrances and odors), touch — and sometimes they can just be sensed.
Steve Ramsey, PhD. Paranormal Investigator , cleanser , South Alberta.