How to Choose a Coffee Machine For Pods Pod machines operate by reading the barcode that is on the top of the pod (which is actually an un-sealed disc of pre-dosed ground beans that are encased between two layers of filter paper). You just insert it and press a button. https://wwwcoffeeeuk83610.blogsumer.com/27993783/how-to-explain-best-pod-coffee-machine-to-a-five-year-old