Desktop Notifications provide a standard way of doing passive pop-up notifications on the Linux desktop. These are designed to notify the user of something without interrupting their work with a dialog box that they must close. Passive popups can automatically disappear after a short period of time.
There are currently some differences between the specification and notification-daemon that need to be fixed but as notify-sharp follows notification-daemon's behaviour instead of the specification's there should be no problems in the future.
In the future, properties for new, standardized hints will be added.