Cross type Auto Focus on camera

A camera's autofocus system intelligently adjusts the camera lens to obtain focus on the subject, and can mean the difference between a sharp photo and a missed opportunity. Despite a seemingly simple goal—sharpness at the focus point—the inner workings of how a camera focuses are unfortunately not as straightforward.

I just find out that the cross type AF point is darn difference.
This is the vid for the 5D mark iii cross type AF point.