Why observable is used in angular?

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Tags

1. #simply
2. #means
3. #subscribe
4. #other
5. #using
6. #promises
7. #differences
8. #observable
9. #similar
10. #method
11. #object
12. #observer
13. #observe
14. #action
15. #registered
16. #acted
17. #pattern
18. #objects
19. #which
20. #angular