# Promise vs Observable

| `Promise`                              | `Observable`                                                                   |
| -------------------------------------- | ------------------------------------------------------------------------------ |
| Produit une seule valeur.              | Produit un "stream" de valeurs *(potentiellement infini)*.                     |
| Non annulable.                         | Annulable.                                                                     |
| Traitement immédiat.                   | Lazy : le traitement n'est déclenché qu'à la première utilisation du résultat. |
| Deux méthodes uniquement (then/catch). | Une centaine d'opérateurs de transformation natifs.                            |


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