Lens coatings are meant to protect your eyes from light or increase lens durability. Five common treatments to know about: Anti-scratch, Anti-reflective, Ultraviolet protection, Photochromic, Blue-light-blocking. Also read about the different types including gradient, HD and others.
Polarized lens are usually made from a chemical film that is applied to the surface. The film will have molecules that are parallel to each other and when applied they will create a filter that absorbs any light matching their alignment.