From Tutorialzine –Quick Tip: The Easiest Way To Show Browser Notifications:
The JavaScript Web Notification API allows both desktop and mobile browsers to display notifications with custom content. Although it’s support used to be quite inconsistent, the API is now compatible with most modern browsers and we are already seeing it implemented in many websites and apps. In this article we will show you the quickest way to set up browser notifications using the open-source Push.js library.