This document discusses web push notifications and how they work. It explains that notifications can appear directly on users' desktops when they click to opt-in. Users can then receive push notifications from sites at any time about updates. Some use cases mentioned are sending manual alerts, auto notifications, integrating with content marketing, and sharing promotional offers. The value proposition discussed is building audiences faster through push notifications which have a much higher opt-in rate than email on average. Browser support for push notifications from the major browsers is also summarized.