Details: This poster says at the top The Most Functional Word in the English Language. Well, it's shit?that's right, shit! There are several examples of uses of the word shit. At the bottom it says Well, shit happens.
Shit is a vulgar word in Modern English denoting feces. It is a native English word, but Latin terms for many common objects and bodily functions came to be seen as more distinguished than native words, and thereafter feces became the accepted English noun, to defecate became the accepted English verb, and shit was no longer used in polite company.