in chapter-05 ring geometry is 2d geometry not 3d

[HyunmokMoon]

https://threejs.org/docs/#api/geometries/RingGeometry

from document, ring geometry is 2D geometry, not 3D.
file name 03-basic-3d-geometries-ring.html, 08-basic-3d-geometries-ring.html
should be change to 2d.
I confused about this. I saw example. Only 2D geometry.
There is no 3D Ring geometry. I think this is maybe torus geometry.

Thank you.