If you're new, you'll likely be doing plenty of extract brews. If that's the case, efficiency won't come into the equation at all since all the sugars you need are already taken care of. When you start to do all-grain brewing you'll need to have an idea of the efficiency of your system and process so you can follow a recipe and know whether your resulting ABV will be closer to 4% or 6%, for instance.I'm new in this art