26 Apr A Grammar Blog–“your” and “you’re”

An apostrophe in the middle of a word means that one or more letters have been left out, and so the apostrophe can be regarded as taking the place of the left-out letters.

So it is with “you’re”, which is a short form of “you are”, in which the apostrophe replaces the a.

“Your” is a possessive pronoun–as in your lawn, your book, your life.