How does push notification work in iOS?

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Tags

1. #device
2. #propagates
3. #service
4. #those
5. #apple
6. #notification
7. #prepares
8. #devices
9. #which
10. #having
11. #target
12. #application
13. #pushes
14. #applications
15. #arrives
16. #registered
17. #provider
18. #notifications
19. #sends
20. #receive
21. #channel
22. #through