How to Choose a Coffee Machine For Pods Pod machines operate by reading the barcode at the top of the pod (which is actually an un-sealed disc of pre-dosed ground coffee that is pressed between two layers of filter paper). Simply insert it into the machine and push a button. https://coffeee77535.newsbloger.com/28843878/9-what-your-parents-taught-you-about-best-pod-coffee-machine