How to Choose a Coffee Machine For Pods The pod machines read the barcode at the top of the pod (which is actually a sealed disc pre-dosed ground coffee that is pressed between two layers of filter paper). You just insert it and press the button. Inject an espresso pod, https://www-coffeee-uk87505.activablog.com/27947176/beware-of-these-trends-concerning-best-pod-coffee-machine