Resources are like services, but are external to your application and which your application communicates with over a network.
Examples of typical resources used with Convox are data stores like RDS or redis, mailservers, and so on.
Resources are typically stateful services.
Resources correspond closely to the twelve-factor app notion of backing services.
A service is a component of your app, defined as a command run against an image. An app is composed of one or more services, e.g.