Roast & Ground Coffee Beans ...
For Coffee Machines without Bean Grinders:
Different types of coffee machine (Espresso, Perculators, Pour-Overs, Caffetieres, Vending Brewers, etc) use different methods to extract liquid coffee from coffee beans.
The coffee bean grind, on a scale of fine to coarse, is, of course, an absolutely essential factor in any coffee machine's extraction process.
Choosing the correct grind of coffee is therefore critical if you want to experience coffee from your coffee machines at it's absolute best, every single time.