1. One person is the "answerer"
2. Everyone else is a "questioner".
3. The answerer begins the round by declaring "I'm thinking of an object!"
4. The answerer names the object's category.
5. The categories are Animal, Vegetable, and Mineral.
6. "Animal" includes any object that comes from animals, including wool sweaters, milkshakes, and powder horns.
7. "Vegetable" includes anything made from plants, such as wood, cotton, tobacco, and chocolate.
8. "Mineral" includes anything of geological origin, like gold, salt, or gunpowder.
9. Some versions of the game include "Other" as a category. I suppose this might include abstract concepts, plastics, and Michael Jackson.
10. The questioners ask yes/no questions about the object.
11. The answerer answers, yes or no.
12. It's possible that the answer might be "maybe".
13. The questioners ask a total of twenty question.
14. That's why the game is called "20 Questions".
15. Questions that cannot be answered by yes or no (such as who or what or how) are ignored.
16. Those questions (being unanswered) do not count against the 20.
17. The person that correctly guesses the object in mind gets to be the answerer for the next round.
18. If nobody can guess the object after 20 questions have been asked, the answerer may think of a new object for another round.
19. This game was played in Charles Dickens' "A Christmas Carol."
20. The object in mind was Ebenezer Scrooge.