So essentially they have the same number and type of atoms, but they differ in their arrangement of those atoms in the three dimensional space. And notice that these are not examples of enantomers, because if we draw a line here, they will not be mirror images. And so what that means is, if they're not mere images, they're not an answers, they must be disregards. And so these are two examples of diaryoisomers. And notice that these are both the Dtype molecule, the deisomer, because this green hydroxyl group found on the final stereogenic carbon, the farthest away from this aldehyme group, points to the right side. Remember, in the deisomers, the hydroxyl group found on the last theogenic carbon points to the right side.