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Do you understand classes, let's understand object oriented programming now, depending on your level

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of knowledge and if you worked with modern JavaScript, that maybe also some other programming languages,

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you might be aware of what Claus's hardware for and what OPIS object oriented programming is all about.

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So Darfor, you can also skipped his lecture to jump right ahead to the part where we write code.

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Otherwise, definitely stick with me because it is important to understand this.

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The idea behind object oriented programming and classes will be important for that, as you will see,

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is that you work with real life entities in your code.

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You could say so.

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Did you work with things in your code with objects that resemble real life objects as far as possible,

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at least to make it easier for you as a developer to reason about your code?

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For example, we might be building an online shop and there we might have a product list.

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We might want to work with a product list, object data for which has everything we need to manage a

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product list.

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A method to add products to the lead products.

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The list itself.

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So for example, this might be an object that is responsible for rendering a list of products and for

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managing it, which were fetched from a service, from a database.

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So this product holds all the rendering and fetching and management logic.

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Now that's a product list in our program into Web site we're building.

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We might also need to work with the individual product, though, so we might all the one that object

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or multiple objects, one for each product that is responsible for managing this single product.

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It might hold and render the details about that product, maybe allow us to add it to a cart.

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Things like debt.

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So when we want to draw a user interface to the screen, we want to manage that through JavaScript and

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deafer for typescript.

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Then we could implement it with a product list and a product object which hold the logic for managing

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the underlying data, but all for rendering the content on the screen.

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And of course, Stanford, these two objects would kind of be related.

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We might also have a shopping cart object on our screen, which is responsible for rendering and managing

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the shopping cart.

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It's of course, also connected to the product and therefore it holds all the logic we need to render

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our shopping cart, placing orders and communicating with the server and so on.

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So that would be one way of how we could think about the applications we're building, how we could

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split it into logical pieces.

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That makes sense to us as humans and encode in typescript and JavaScript in most modern programming

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languages.

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Does this actively supported because we have objects which are more complex data structures that hold

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properties and methods.

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And of course we do have that in JavaScript as well.

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But we might also have classes that help us with that.

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Now, what's the idea behind classes and what are incenses?

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Well, we've got these objects and when following does object oriented approach, we could consider

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splitting our app or our application logic into such objects which manage parts of our logic.

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Now, connected to the idea of using these objects, which of course do exist in JavaScript, we can

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use objects.

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There is the idea of having classes.

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Objects are the concrete things we work with in our code.

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The data structures we use to store data, to store methods to execute methods on classes are blueprints

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for objects.

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Classes allow us to define how objects should look like, which data they should hold.

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Which methods they should have so that we can easily build objects based on these classes.

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And we then called this instances off the classes.

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So an object then is an instance of a class.

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If it's based on such a class so that we can quickly replicate multiple objects with the same structure,

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the same methods based on the same classes.

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So classes help us define how objects should look like, which properties and methods to have and so

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on.

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So classes exist to speed up the creation of objects and it's simply an alternative to using the object.

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Literal notation, you already know.

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They simply make it easier.

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Classes simply make it easier to create multiple objects, which generally have the same structure and

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the same efforts, which might only defriended exact data details which are stored in there.

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Let's say we have multiple persons we want to represent with objects.

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While each person might have a name and a H, the values will differ.

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The general structure is the same.

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So that's the theory.

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Let's see it in practice.