Subdivision Surfaces

A subdivision surface is a polygon mesh that has been divided into more faces while retaining the object's general shape. You perform subdivision to add detail to an object, or to smooth it out.

OpenSubdiv modifier with Iterations = 0, 1, 2, 3 (left to right), creasing down centerline

3ds Max supports three kinds of subdivision surfaces:

The latter type works best as a finishing tool for models.