1955 era joke

  It's the summer of 1955 and Bobby goes to pick up his 
 date, Peggy Sue.
  Bobby's a pretty hip guy with his own car and a duck 
 tail hairdo.  When he goes to the front door, Peggy Sues'
 father answers and  invites him in.
  "Peggy Sue's not ready yet, so why don't you come in and 
 have a seat?" He says.  "That's cool." says Bobby.
  What are you kids planning to do, asked the father?
  Bobby replies politely that they will probably just go 
 to the malt  shop or to a drive-in-movie.
  Peggy Sues' father responds, "Why don`t you kids go out 
 and screw? I hear all of the kids are doing it."
  Naturally this comes as quite a surprise to Bobby and 
 he says "Whaaaat?"
  "Yeah," says Peggy Sues' father, "We know that she likes 
 to screw;  why, she`d screw all night if we let her!"
  Bobbys' eyes light up and smiles from ear to ear. 
 Immediately, he has revised the plans for the evening.
  A few minutes later, Peggy Sue comes downstairs in her 
 little poodle kirt with her saddle shoes and announces that 
 she's ready to go.
  Almost breathless with anticipation, Bobby escorts his date 
 out the front door while Dad is saying, "Have a good evening 
 kids," with a small wink for Bobby.
  About 20 minutes later, a thoroughly disheveled Peggy Sue 
 rushes back into the house, slams the door and screams at 
 her father:

 "DAMMIT DADDY! The TWIST!!! IT`S CALLED THE TWIST"!!!