The Keurig k cups are the body and soul behind Keurig's innovation. Every one is separately sealed for freshness, and within is a paper filter filled with coffee grounds.
The Keurig Coffee Maker puts a hole in the top of the cup and a hole in the bottom. The water passes through the coffee premises and through the filter. The brewed coffee then comes out the hole at the bottom and into your mug below.
learn more about Single Serve Coffee cups here