Ghosts really freak me out!  Do you believe in ghosts?
Why not? Ghosts are known as an apparition, phantom, shade, specter, spirit. They are thought to be the soul of a dead person or animal.
Have people throughout history always wonder if ghosts were real?
I am sure they have considered it. The attempt to contact the spirit of a deceased person is known as necromancy.
Necromancy is a creepy sounding word!  Is there any evidence to the validity of ghosts or spirits?
Necromancy
Necromancy () is a practice of magic involving communication with the dead – either by summoning their spirit as an apparition or raising them bodily – for the purpose of divination, imparting the means to foretell future events, discover hidden knowledge, to bring someone back from the dead, or to use the dead as a weapon. Sometimes referred to as "Death Magic", the term may also sometimes be used in a more general sense to refer to black magic or witchcraft.
The word "necromancy" is
Ghost
In folklore, a ghost (sometimes known as an apparition, haunt, phantom, poltergeist, shade, specter or spectre, spirit, spook, and wraith) is the soul or spirit of a dead person or animal that can appear to the living. In ghostlore, descriptions of ghosts vary widely from an invisible presence to translucent or barely visible wispy shapes, to realistic, lifelike forms. The deliberate attempt to contact the spirit of a deceased person is known as necromancy, or in spiritism as a "séance