The word "ghost" comes from the old English word "gast" and originally had nothing to do with spooks.  It meant the life force.  Then it took the meaning of "breath," which is one of the signs of life.  Later, people used it to mean the soul or spirit, the part of a person that is believed to live on after the body dies.  But nowadays, it means the soul or spirit of a dead person who returns to visit the living for purposes of both good and evil, but, most of the time, evil.

There are six kinds of ghosts: Replay Ghosts, Revenge ghosts, crisis ghosts, poltergeists, animal ghosts, and Phantom traffic.

Most ghosts wear clothes.

Ghosts are allergic to silk, salt, and running water.

If you are the 7th child of the 7th child you have power to see ghosts. 

Also if you are born between Midnight and 1 am you can see ghosts too.

Ghosts often haunt crossroads.