Difference between Observable and Promise?

Question

Accepted Answer

Observable is for handling multiple values over time, while Promise is for handling a single value.

Observable can emit multiple values over time, while Promise can only emit a single value.
Observable can be cancelled, while Promise cannot be cancelled.
Observable provides operators for transforming and combining data, while Promise does not have such operators.
Observable is lazy, meaning it won't start emitting values until someone subscribes to it, while Promise starts executing immediately.
Observable can handle errors by providing an error callback, while Promise handles errors using the catch() method.

Accepted Answer

both observables and promises help us to work with asynchronous functionality in javascript. promises deals with one asynchronous event at a time while observables deals with a sequence of asynchronous events over a period of time.

Accepted Answer

Promise	Observable
emits a single value and called only once	emits multiple values and called multiple times over a period of time
not lazy requests gets fire even if we remove then	lazy requests are not fire if we remove subscribe
Can not cancel promise	can unsuscirbe observable using unsubscribe() method

Difference between Observable and Promise?

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