Ghost Hunters is the best ghost show on tv. I actually do believe it is legit. But Most Haunted, as Volke said, is pathetically fake. It's just a bunch of British people in a dark room going "Ahhh!" "Oooh!" all night. If you didn't see the picture, you could swear it's porn.
Anyway, I also believe in ghosts/spirits. As with things like Bigfoot, aliens, and the Lock Ness Monster, there is simply too much evidence for there not to be some grain of truth to it.
I won't get into the debate about what ghosts are, as we clearly don't know for sure. They could be anything from energy to actual souls of humans trapped on earth. However, there is plenty enough video, audio, and photographic evidence to prove that ghosts exists. They can't all be hoaxes, there are too many claims for that. Not everybody is a liar.
My personal take on it is this:
There are several different types of paranormal entities. Psychic imprints that are reflections of past trauma or signifigance (i.e. "residual hauntings") which I believe make up the bulk of paranormal phenomenon. Then you have actual spirits that can interact with people & objects, and manifest themselves. Intelligent hauntings. Then you get into the way out there stuff like poltergeists (more than likely mischievous or evil spirits), demons, angels, etc. which require no explanation.
I've personally had a few paranormal experiences in my lifetime, nothing monumental by any stretch of the imagination, but enough to believe that there could be ghosts & spirits.
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