The Cordova Connection object provides an application with information about the current network connection available on the device (and available to the application).
An application would use the Connection object to help it determine if network connectivity is available as well as the type of connection that is available. If the application had data to upload to or retrieve from a server, knowing whether the connection is available will help the application to determine whether or not to begin the transfer. If an application is working with a large amount of data that it needed to upload to or retrieve from a server, the ability for the application to be able to tell what type of connection is available will allow it to only perform this large update when a less expensive (Wi-Fi) network connection is available.
The chapter includes a sample application that illustrates how to use the Connection API in a Cordova application.