Also see ghost imaging.
Ghost is a software product from Symantec that can clone (copy) the entire contents of a hard disk to another computer's hard disk or to storage media, automatically formatting and partitioning the target disk. This product is especially useful where one system is to be replicated on a number of computers or when someone wants to back up everything on their personal computer.
On the Web's live chat medium, the Internet Relay Chat (IRC), a ghost is a vacated user session that the server believes is still active.
The word "ghost" derives from Old English gast and means a disembodied spirit or soul.