Your = Belonging to or associated with the person or people that the speaker is addressing: "Your bad grammar is killing me inside, not because of your improper usage, but because of what it implies of your lacking awareness of how your grammar affects your image".

You're = Contraction of you are: "You're probably not going to think that these definitions matter much if you're not already aware of them, and you're probably going to want to flame me for making a big deal about it, but if you take notice of when you use each of these terms, you're going to seem more mature and intelligent. People will take what you say with greater weight." Notice the apostrophe between the u and the r. It's not a decoration.

Yore = Time long past: "Do you remember in the days of yore, when a woman could just look down and see that you have a huge schlong, thereby getting you a lot more poon tang than you can get now with all of these clothes on?"