How to Choose a Coffee Machine For Pods Pod machines operate by reading the barcode on the top of the pod (which is actually a disc of sealed, pre-dosed ground coffee that is pressed between two layers of filter paper). It is easy to insert it and push a button. https://coffeeeuk27557.madmouseblog.com/8787552/10-tell-tale-signs-you-need-to-know-before-you-buy-best-pod-coffee-machine