James Madison wrote the 10th Essay in the Federalist Papers. He detailed information about segments/groups within the population, what were they "specifically called," what are they specifically called now? What is the significance of this Essay? Who gets the most and the least in the United States today? Why?

Here is the text: The Federalist Papers, #10.

Madison spoke of controlling the violence of "factions"; "a number of citizens, whether amounting to a majority or a minority of the whole, who are united and actuated by some common impulse of passion, or of interest, adversed to the rights of other citizens, or to the permanent and aggregate interests of the community."

"Faction" is still used today, but the more general "movement", I think, is used more frequently.

I will leave it to you to read the text for an answer to your 3rd question.

As for your 4th question; what do you mean? Who gets the most what?