What is the difference between promises and observables?

Related questions

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4. What is reactive data access?
5. What is Cocoa framework?
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7. What is the use of RxSwift?
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Tags

1. #emits
2. #single
3. #difference
4. #could
5. #multiple
6. #observable
7. #operation
8. #asynchronous
9. #promise
10. #value
11. #iterable
12. #between
13. #values
14. #whereas