system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are some words in English considered "rude" or "obscene" but their synonyms are not?

ie. Poop vs Shit or Crap

I know it varies by region/culture but that's about it.
gpt
One theory is that it boils down to prejudice against vulgar language.  

Notice that the rude words are mostly of old English origin, words like shit, cunt and dick, whereas the polite terms are of French or Latin origin, such as faeces, vagina and penis.  

England's elites used to speak French or Latin.  They were deemed the "polite" society.  The poor were deemed to be vulgar, hence "rude" or impolite.