The easiest way to remember which word to use is to remember that you're is a contraction of the words you are. You're = you are. Keep this in your mind if you get a little stuck. Whereas, your = belonging to a person.

What is difference between your and you re?

Your is a possessive adjective. It is always followed by a noun in a sentence. You're is a contraction of two words, “you” and “are.” Contractions can be easily recognized by the apostrophe. Generally, contractions are not used in academic and formal papers and documents.

Is it your so pretty or you re?

The correct form is obviously "you're". You're beautiful! However, "Your beautiful!" sounds the same as the contraction "you're", and it's so common on the net that sometimes I even think it actually looks better, LOL.