Poltergeist comes from a German word meaning "noisy spirits." Reports of poltergeists date back to Ancient Roman times. The activity starts with knocks and bangs then possibly furniture moving around by itself. Then, as the poltergeist gains confidence, the activity is intensified, making itself known through voices and even appearing as a full apparition. 

Many television shows choose to show this style of haunting because it tends to be the most terrifying and rarest type of haunting that occurs.

The most common person this type of activity happens around is a female in her teen years. Some of these cases seem to be caused by the female, unknowingly, and subconsciencely, controlling the energy around herself. In other cases, it can happen around people that are stable and in their right state of mind.

This haunting is hard to classify due to certain situations. No two hauntings are ever alike. Most of the time you will find that one person in the household seems to be more affected by the haunting than anyone else. It may seem that most of the activity doesn't happen unless that certain person is present. If this is the case, the activity will stop when that person leaves the home.

The majority of the time poltergeists are experienced by more than one person in the household, but again, the activity will center around one certain person. This person may be highly stressed as of late or emotional distress. If you find that to be the case, seek medical care for that individual, and soon afterwards, the poltergeist activity will subside.

When it is not the female teenager that is manifesting the activity, there are usually several spirits in the area. Spirits will "pool" their energy together in order to become strong enough to move larger objects and make more noises. In order to calm them, you will need to find the root of their anger to help them pass over and leave you in peace.

On most poltergeist cases, they will disappear without any warning, just as they appeared. Certain times it may stop within a few days, other times it may take years. You may never know the reason that it happened. Most people are just happy to see it go and that's enough for them.

Lastly, by understanding why it was there in the first place, helps you to understand how to keep it from ever coming back again. Knowledge is the key in protecting yourself in this world.