Are Demon Possessions and Exorcisms in the New Testament Literal?

Questions about whether references to demon possessions and exorcisms in the New Testament are literal, how to talk to young children about ghosts, and whether it’s arrogant to think Satan knows your name when he’s a single entity with bigger fish to fry.  

• Are references to demon possessions and exorcisms in the New Testament literal, or are they cultural references to physical or psychological conditions that they didn’t understand?
• How do you talk to young children about ghosts? It’s tempting to say they aren’t real, but I don’t want to deny the reality of “spiritual forces of evil” (Eph. 6:12).
• Is it misguided or arrogant to think Satan even knows my name when he’s a single entity with bigger fish to fry than me and can only be in one place at a time?