When I first watched a video I have no idea what they were talking about then they said they are puting shadow on the outer V. Now I do and know all these terms from mostly practice and constantly watching tutorials. It is crazy how you can break up the eye into like quadrants. But it makes it much easier for the artist.
Here is a way to do your shadow in a way that is appealing. By using certain shades in certain areas for a better look over all. You DON’T want to get these mixed up. My sister did when she was in high school. She would put the darker shade on her brow bone area and the lighter shade on the bottom.