Faced insulation has kraft paper attached to it, which enhances its sturdiness and prevents it from falling. Unfaced insulation lacks this paper but performs similarly.
Insulation works by slowing conductive and convective heat flow, while radiant barriers and reflective insulation reduce radiant heat gain through reflective surfaces in contact with air spaces.
Mineral wool is a fiber insulation made from natural materials, similar to fiberglass but not from glass.