Using Local And Push Notifications on iOS and Mac OS X

Local and push notifications let background or inactive apps notify users that an event of interest has occurred, or that an app has new information for them. See how to use notifications to display a message, play a distinctive sound, or update a badge on your app icon. Understand how to register for push notifications, learn how to schedule local notifications, and discover the best practices for handling both.

WWDC 2011 - iOS, macOS