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 beans that are encased between two layers of filter paper). Simply insert it into the machine and push a button. https://wwwcoffeeeuk83428.total-blog.com/the-biggest-issue-with-best-pod-coffee-machine-and-how-you-can-resolve-it-53556131