What is the difference between Observables and Subject?

Question

Accepted Answer

Observables are streams of data that can be observed, while Subjects are both observers and observables.

Observables are unicast, meaning each subscribed observer receives its own stream of data.
Subjects are multicast, meaning they can have multiple observers and share the same stream of data.
Observables are cold, meaning they start emitting data only when subscribed to.
Subjects are hot, meaning they start emitting data immediately upon creation.
Observables can be transformed and combined using operators like map, filter, and merge.
Subjects can act as event emitters and can be used to broadcast events to multiple subscribers.

Accepted Answer

In short, an Observable is a stream of data that can be observed by multiple subscribers. It emits data over time, and subscribers can react to these emissions by defining handlers or operators.

On the other hand, a Subject is a special type of Observable that can act as both a data source and a subscriber. It allows you to push data to multiple subscribers, similar to an Observable. However, it also allows you to manually trigger emissions by calling its next() method, making it useful in scenarios where you need more control over when and what data is emitted.

What is the difference between Observables and Subject?

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