Here’s another by-request post, the subject of which you’ve already guessed. (I’m sure of this. You’re smart people.) I know I did a usage tip about this within the last year, but it’s been lost to the sands of time (and Google), so . . . once more into the breach, dear friends.
Your. You’re. Yore. Two of those are personal pronouns. One is a noun. (And, honestly, I don’t see the noun confused for the pronouns very often, myself — but the issue was brought up, so I’ll discuss it. That’s how I roll.)
Your is the second-person singular and plural possessive pronoun. “Watch your step.” It denotes a thing belonging to “you,” whether “you” is one person or many people. (I’ve written before about “thee/thou” and “ye.” Modern English has no separate second-person singular pronoun. “Thee/thou” went out of style. It’s all you, as they say.)
You’re is the contraction for “you are.” (I know you all know this, too, but I’m something of a completist so I’m saying it all again.) The apostrophe replaces the “a” from “are.” When you see an apostrophe, you can be sure the word is either a possessive or a contraction. (There are a very few exceptions to this, but that’s a different post, I think. I don’t want to muddy the waters here.)
Yore is a noun meaning “time past and especially long past.” (Thank you, Merriam-Webster’s Online Dictionary.) Nowadays it’s often used in a mock-nostalgic sense. It is also noted as being “chiefly literary.” In other words, you aren’t likely to find it in an article in Time Magazine. Interestingly, yore was an adverb in Middle English, but a noun in Old English. I’ll let you poke around on the internet and find out the details for yourselves if you’re so inclined.
I’ll also note here that I’ve never gotten a request about your/you’re that included “yore” from a US writer — only from those in the UK or Canada (so far). I’m not sure what that says, aside from “US writers do not appear to be prone to using the word yore.”
In days of yore, your daily bread was made from grain you grew yourself. You’re in a much better position today, I dare say.