[angular] What is the difference between Promises and Observables?

Promise:

  • Provide a single future value;
  • Not lazy;
  • Not cancellable;

Observable:

  • Emits multiple values over time;
  • Lazy;
  • Cancellable;
  • Supports map, filter, reduce and similar operators

You can use promises instead of observables when calling HTTP in Angular if you wish.

Examples related to angular

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Examples related to rxjs

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Examples related to angular-observable

What is the difference between Promises and Observables?