Why do we need an Observer?

Observer is an object which monitors or observes something continuously and it notifies after something is changed .

Being a good observer enables us to take a step back and peer into ourselves and others . Just looking produces nothing. Observing produces insights when we assess for patterns, styles, and results. Why observing matters is centered here – discerning patterns, styles, and results.

Observer is a behavioral design pattern that allows some objects to notify other objects about changes in their state . The Observer pattern provides a way to subscribe and unsubscribe to and from these events for any object that implements a subscriber interface.

Observer is a behavioral design pattern . It specifies communication between objects: observable and observers. An observable is an object which notifies observers about the changes in its state. For example, a news agency can notify channels when it receives news.