If you really want to impress people, start talking about tempering chocolate. And really know what you mean. Need some help with that "actually understand" part? Here, let me educate you.
Do you need to temper chocolate? It depends. Chocolate chips, chocolate candy coating (which contains some type of wax), or candy coating chips do not require tempering, as they have already been treated. If you are working on very small decorations, or will be painting over chocolate, chances are it is not necessary. However, when gloss is important, tempering is what separates the amateurs and the pros. Tempering is a method of heating and cooling a substance to improve its texture and durability. It’s used for many different substances, including metals. But on the food and cooking front, when you refer to tempering, you’re probably talking about chocolate. When you temper, you first raise the heat, making the chocolate melt, then reduce the heat, letting it cool. When it cools, stable crystals of cocoa butter form. When brought back to a working temperature after this process has occurred, this is what allows the perfect snap on a candy bar, and the impeccably glossy, smooth texture on candies and finished baked goods.