Have you ever heard the term “filter coffee?” We say it in the cafe sometimes, and maybe you’ve heard it elsewhere. Coffee brewing essentially breaks down into two categories: espresso and filter. To understand filter coffee you have to understand basic filter theory. We’re going to go over just a few basic principles to launch you into the world of filter.

Coffee has been around a long time, and with anything that's been around awhile, there are quite a few rumors and ideas bouncing around about it. So for coffee's sake, we want to set the record straight about a few things.

Water is extremely important in coffee-brewing (it is the majority of the beverage, after all). While brewing, the hot water extracts tastes from the grounds to turn plain water into delicious coffee. This happens through chemical bonding, where the particles in the coffee bond to the particles in the water. Differences in water can disrupt this process and undermine the deliciousness of the coffee. There are two common problems people make with water choices, and both are easily avoidable.