Push notifications are text or rich media messages sent to a user's device or a web browser. They are used to provide convenience and value to app users and can be triggered locally or sent from a third-party service when the app is not running.
This is a companion discussion topic for the original entry at https://blog.crowdbotics.com/push-notifications-why-you-want-them-and-how-to-build-them-into-your-app-part-1/