The sagittal plane divides the body into a left and a right section and runs vertically from top to bottom. If the plane runs directly down the midline of the body and thereby equally divides the body into left and right sections, the plane is referred to as a mid-sagittal or median plane. If the body is unequally divided, not running down the midline of the body, the plane is referred to as a para-sagittal plane.

Image 1: Human model divided into a left and right section by two different sagittal planes: the mid-sagittal and para-sagittal plane