An exciting feature used with Angular is the Observable - utilized via RxJs. Observables aren't an Angular specific feature, but rather a proposed standard for managing async data that was originally slated for the release of ES7 - However, it still is not standardized, which is why libraries like RxJS are essential. Observables open up a continuous channel of communication in which multiple values of data can be emitted over time. From this we get a pattern of dealing with data by using array-like operations to parse, modify and maintain data. Angular uses observables extensively - you'll see them in the HTTP service and the event system.