If you opened a school textbook from the 15th century, you might be surprised to see how some familiar actions and parts of the anatomy are described. Though words like fart and s--- would be considered too crass, or even silly, to educate children with today, in those days they were simply an acceptable part of language.
And if you time traveled back to medieval London, you might stumble across some curious street names, too. Naming an alley after how many people urinate there — in this case, the unfortunately on-the-nose "Piss Alley" — might just seem plain vulgar to folks today.