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So guys, now we will going to discuss the concept of notification chains.

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So notification chains is all about notifying the subscribers about the events.

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So now let us quickly discuss what notification chains are and how do they work.

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So notification chain is an architectural concept and used to notify multiple subscribers interested

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in a particular event.

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Right.

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So note that it is an architectural concept or you can say it is something that can be implemented in

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any programming language.

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In other words, it's a design pattern.

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A party which generates an event is called a publisher.

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And parties which are interested in being notified of the event are called subscribers.

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Right.

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So need not worry.

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We will going to understand it with the help of an example.

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There is always one publisher and multiple subscribers.

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Shortly we will going to discuss what exactly publishers are and what exactly subscribers are and what

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exactly these events are.

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Right.

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Once the event is generated or produced by the publisher.

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Right.

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So note that events is something which is generated or produced by the publisher.

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The event is pushed to the subscribers which are interested in this event.

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Right.

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Subscribers can register and register for the event with the publisher at their will.

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And publisher subscribers could be any entities.

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They could be multiple threads of the same process.

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They could be multiple processes running on the same system, or they could be multiple processes running

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on different systems, or in fact they could be different components of the same big software system,

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right?

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So there is absolutely no constraint as to who can be publisher and who could be subscriber.

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The publisher subscriber could be anything including thread process, running on the same system or

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processes running on the different system or different components of the same big software system running

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on the same machine right now.

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Let us try to understand technically what publishers and subscribers and events are.

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So basically notification chain is all about communication between publishers and multiple subscribers.

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Notification chain is important because this is one of the most important and common communication pattern

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which you will definitely come across when you will be working in the industry.

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It is not uncommon to find this type of communication pattern between different entities and therefore

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I have included it as a part of this course.

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Now, in the next lecture video, we will going to have pictorial representation regarding how publishers,

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subscribers and events are related to each other.