Poltergeist:

 This means noisy ghosts or an angry ghost who cannot accept they are dead. The easiest target is children since feeding off its fear gives it energy, momentum, & the attention it wants. Poltergeist are said to move objects, bite, growl, scratch, scare, hit, push, vandalize, start fires & so much more. Poltergeist are also the ghosts we create with our mind like a false ghost our minds create when usually our brain is overwhelmed (a form of psychosis). Nobody is sure if these are even ghosts or souls. They may be an entity of some other kind, not as bad as demons perhaps, but they will scare you. Poltergeist are usually thought of as very violent spirits who would feed off of your fear & grow in power. However new studies show that its very possible they are manifestations of our own psychosis. Meaning, John Doe is real stressed out & perhaps he keeps his emotions in. Well his brain manifests these emotions into the form of objects violently flying in a room, voices, things of that sort.