system
Given the following post, respond as if you're commenting on Reddit:
human
[Lord of the Rings] what exactly is the difference between Numénoreans/higher races of Men and other races of Men, and how did this division come to pass?

I've always found the concept intriguing but I don't really get the multitude of racial differences in LoTR.  Specifically about the races of Men.  Were Numénoreans/higher races the first Men? Why are they different? What about them is different compared to other Men? Was there a time when there was only higher races of Men or have there always been higher and lower? I need to know it all!!! Help me Reddit!
gpt
There are technically four types of men. 

The Edain/Numenoreans/Dunedain - They are the "high" race of men. The original Edain who fought against Morgoth in the First Age were blessed and became Numenoreans. Numenoreans were superior to other men in every way (height, strength, culture, lifespan and an immunity to sickness). The Numenoreans grew powerful, eventually becoming the most powerful nation in the world. They established colonies all throughout Middle Earth and at first, they had a cordial relationship with the men who lived in Middle Earth. However, as their power grew, so did their arrogance, cruelty and most importantly, their longing for immortality. As their faith in the Valar started to decline, so did their superiority and by the time of the Fall of Numenor, the Kings of Numenor who had once lived to over 400 years of age now barely lived past 200 years of age and all Numenoreans lost their immunity to sickness. When Numenor fell, the survivors (the ones who were still faithful to the Valar) became the Dunedain and founded the Kingdoms of Gondor and Arnor. Although they regained some of their strength, they've slowly been in decline throughout the Third Age. Aragorn is a pure-blooded Dunedain and lived to over 210 years of age, whereas someone like Faramir is mixed blood and lived to just over 130.

It's also worth mentioning that Black Numenoreans are also a thing. These guys are basically Numenoreans who became loyal to Sauron. Very few actual Black Numenoreans still exist as most of them intermingled with the Haradrim and became the Corsairs of Umbar. It's possible that the Corsairs may have retained some of their Numenorean ancestors traits. 

Middle Men - Middle Men are men who were related to the original Edain and either didn't cross into Beleriand during the First Age or didn't go to Numenor. Middle Men include Bree-landers, Rohirrim, Northmen, Dunlendings, Hill-men and Druedain. Although they're all technically Middle Men, they're mostly pretty different from each other. Bree-landers, Rohirrim and Northmen are all pretty civilised, whereas Hill-men, Dunlendings and Druedain are pretty much barbarians. Whereas Numenoreans are superhumans, Middle Men are pretty comparable to modern humans in most physical aspects. 

Men of Darkness/Twilight - These guys are pretty much the same as Middle Men in most ways except for the fact that they worship Morgoth/Sauron. They include the Haradrims, the Easterlings and the various other men that live throughout Middle Earth. They didn't descend from the Edain and generally hate the Dunedain and their allies. 

Hobbits - Hobbits are technically Men. It's not really known how they became the way they are, but biologically they aren't really their own race like Elves and Dwarves are.