I am fairly sure that most people have heard the term LOW-E glass or LOW-E windows. It is one of those new-fangled ideas that helps. Right? Well yeah it is fairly new and honestly high tech.
What does LOW-E actually mean? A LOW-E window is one whose Emissivity of Heat is Low. Or, a Low-E window cuts down on the Emission of Heat, along with other things, all of which are good.