Coffee cupping is a term that is used to taste multiple coffees while having the least possible variables. Cupping is used by suppliers to find a specific coffee they want or to ensure quality, used by roasters to dictate how the roast is affecting the bean and to create new blends and consumers to enhance their coffee palate.
This method of doing coffee involves multiple small bowls (sugar bowls work best), a soup spoon, fresh coffee, a scale, and a kettle. The goal of brewing is consistency which is achieved by having the same coffee weight, water ratio, and brewing time.
If done correctly, one will be able to sample and taste the multitude of different notes coffee has. If available, it is best to start with 3 distinct coffees that have radical characteristics to be able to tell them apart. As one becomes more experienced, the coffee palate will expand.