In Angular (currently on Angular-6) . subscribe() is a method on the Observable type. The Observable type is a utility that asynchronously or synchronously streams data to a variety of components or services that have subscribed to the observable..
Correspondingly, why do we use subscribe in angular?
This is the function that is executed when a consumer calls the subscribe() method. The subscriber function defines how to obtain or generate values or messages to be published. To execute the observable you have created and begin receiving notifications, you call its subscribe() method, passing an observer.
Also, what is the use of observable in angular? Observable are just that — things you wish to observe and take action on. Angular uses the Observer pattern which simply means — Observable objects are registered, and other objects observe (in Angular using the subscribe method) them and take action when the observable object is acted on in some way.
Also asked, what are services in angular 6?
Angular services are singleton objects that get instantiated only once during the lifetime of an application. They contain methods that maintain data throughout the life of an application, i.e. data does not get refreshed and is available all the time.
What is observable and subscribe in angular 6?
Observable. subscribe() The observable subscribe method is used by angular components to subscribe to messages that are sent to an observable.
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In Angular (currently on Angular-6) . subscribe() is a method on the Observable type. The Observable type is a utility that asynchronously or synchronously streams data to a variety of components or services that have subscribed to the observable.Why do we need observables?
Observables provide support for passing messages between publishers and subscribers in your application. Observables offer significant benefits over other techniques for event handling, asynchronous programming, and handling multiple values. 
