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 a disc of sealed, pre-dosed ground coffee that is pressed between two layers of filter paper). You simply insert it and press a button. https://www-coffeee-uk91567.canariblogs.com/5-laws-that-will-help-the-best-pod-coffee-machine-industry-43684908