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Welcome to brand new section and that is MVC Design Party.

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What is it and why should we care about it?

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Well, let's explain more.

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When we see MVC, it is a design pattern.

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What does it mean?

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Well, as a back end developer or as a programmer, you need a design pattern.

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Simply means that how you write your code, because we have a standard way of writing code.

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So the most popular design pattern in Node.js is what we call the MVC.

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We have many types of design pattern, but in Node.js, MVC is the most popular one.

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So we are going to stick to MVC design pattern, meaning how we can write a better code.

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So let's get started.

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When we say MVC, it simply means model view controller, and this is a design pattern.

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Specify that an application consists of one data model two presentational information and three control

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information, meaning that every application that is back in application comprises of three components.

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One is the data flow inside your application and is being represented as the model and the view represent

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the presentational part of your application.

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And then the C represent what the control information.

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So when designing an application, one can think of the MVC paradigm as dividing the element of your

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application into three groups.

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And the first one is what we call the model.

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So when you say model, what does the mean where any code representing the knowledge or the data in

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your application?

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For example, database entries when seven files or in memory object and all this is what we call the

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model.

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The next component is what we call the view.

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So view represent how models are displayed to the user, meaning how content are being displayed to

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the user.

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A sample of them is eight pages with some embedded JavaScript or XML documents or console.log output.

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All these are what we call the view part of your application.

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And lastly, we have what is called the controller.

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Well, the controller take input from the user and then decide what to do with it based on the predetermined

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or predefined rules.

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An example of this is when submitting a form in a web application.

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So controllers is where our business logic lies.

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So for any application that you are going to build using Node.js, you need to have these components

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and we are going to create an example application to explore or to show you how all these pieces come

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together to form a complete design paradigm.

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Well, so controller is where our business logic lies.

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So again, always the controller.

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Talk to the model, but a controller cannot talk to the view directly.

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So it goes like this.

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Well, we take an action from the controller to interact with our object, meaning our data base here.

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And in case there are some changes, then it will display to the UI for the user to see.

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So in a nutshell, this how MVC design pattern works.

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So the next video, let's get started by building and complete API where we are going to differentiate

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our application into these three components.

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Let's get into that in the next video.