What is the difference between your, and you're?

Your is possession, like that's YOUR coat.
You're is short for YOU ARE. You're just breaks down the two words.

"You" is one word. "you're" is twosuch as: You are. The ' is what separates the two words these are called conjunctions. 

I would say that the mood of a story affects how the reader perceives a story, and what they take from it. When a story has a somber, sincere tone, most readers will take the story more seriously, and pay closer attention to detail, as well as feel empathetic, or melancholic. When a story is more lighthearted and easier to read, I think a reader is more likely to pay attention to rhythm, and diction, and maybe appreciate the satirical aspect of the work.