Ghosts, spirits, apparitions, spooks, specters, haunts . . . whatever you call them, ghosts have provided us with fascinating study material and conversation topics for centuries. However, they've also given people the opportunity to take part in raging debates over the reality of the spirits' existence. Interestingly, the two sides are split about equally, with nearly half of people polled saying they do believe in ghosts, and the other half claiming that strange happenings can always be explained with the help of science. Whether you're a believer or not, the debate and the subjects themselves are certainly intriguing. Let's take a closer look at ghosts and the ways in which they are explained, or in some cases, rationalized.

What are ghosts? To those who believe in them, ghosts are most often thought of as the spirits of a deceased people who, for whatever reason, have not been able to "move on," or leave this world. One of the most popular explanations for why a person's spirit remains is that it has unfinished business that it feels must be resolved before it can move on. For instance, if a person was murdered and the killer was never discovered, the murdered person's spirit may feel it needs to stay on to see that justice is served. Other entities that are also thought of as ghosts include demons or other spirits, including those of animals. Ghost sightings, spiritual communication, and other supernatural activities have been reported and recorded for centuries. Hauntings will often occur in places where people have died or where their bodies rest or in places that were significant to a spirit during its lifetime.

How do people find or study ghosts? People usually don't "find" ghosts; believers in the supernatural claim that most sprits are intelligent beings who act of their own accord. If a ghost wants to be seen, heard, felt, or otherwise studied, it will make itself known; however, if a spirit has no interest in interacting with living people, it simply will not. With that in mind, advancements in technology have been made for the study of supernatural activity if and when a spirit does decide to interact.

Equipment such as infrared sensors, thermal cameras, Geiger counters, digital voice recorders, and more have provided ghost hunters with the means to collect hard evidence that can help determine if paranormal activity is indeed occurring at a specific location. The data that these tools provide can be very helpful to those studying supernatural events, and they also provide a measure of proof that can be used when determining the validity of events. Aside from electronic equipment, there is also something to be said for spiritual mediums, or people who have an apparent ability to communicate with ghosts and other spirit entities. Mediums don't need to rely on tools such as the ones listed above; rather, they use their own innate ability, a sixth sense to interpret paranormal activity. Though there is no scientific proof to back up what a medium senses, they can still provide a great service in the study of the supernatural.

Though there have been several famous mediums over the last couple of centuries, three of the most notorious are the Fox sisters from Hydesville, New York. Beginning in 1848, the girls began experiencing what they and many others believed to be messages from a murdered man who had been buried in the cellar of their home. The spirit used a series of knocks and raps to communicate. News of the haunting quickly spread, attracting visitors from across the United States. It didn't take long for the sisters to become famous, well-known to both devoted believers and doubting skeptics. Though the girls were later exposed as frauds through their own confession, they infused much notoriety into the work of spiritual mediums.

What are some of the other explanations for supernatural events? Opposing the believers, of course, are the non-believers in supernatural events. Non-believers usually deny the occurrence of paranormal events and believe there is always another explanation for strange happenings. To them, strange noises always have a physical source, apparitions are a trick of the mind, and cold spots are nothing more than their name implies - simply a cold area. The story of the Fox sisters provides a great example of how non-believers explain supposed supernatural events. From the beginning, skeptics loudly proclaimed that the rapping sounds from the "spirit" really came from some other source. The most popular explanation among critics was that the sounds came from the girls cracking their knuckles, toes, ankles, or knees. Indeed, this is precisely what one of the girls confessed in later years, admitting that toe cracking was the source of the mysterious sound that had convinced thousands of the presence of a spirit.

So, can ghosts be real? This is a question that may never be answered. Even after hundreds of years of interest and study, there is still not enough concrete proof to convince everyone that haunting and other paranormal events are the work of ghosts and other spirit entities. For every flawless story that seems to provide absolute evidence of a ghost, there is a story like that of the Fox sisters that casts doubt on the possibility of supernatural events. Determining the truth about ghosts may never happen, and the answer to the question really lies in a personal belief about the existence of paranormal activity.