Do you believe in ghosts? If so, have you ever seen one? If you answered "yes" to both questions, you are not alone. In fact, a number of surveys found that the majority of people who took part believe in ghosts, with a high percentage claiming that they have seen them.
The belief in the supernatural is an old one. For millennia, humankind has used it as a source of meaning, and continues to do so to this day. But while many people claim to have had paranormal experiences, science also has a word to say about this.
Click through the gallery to find out why people see ghosts, according to science.