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Hi, everybody, welcome.

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Today, we're getting started with one of the most important topics of the course, which will be one

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of the most challenging as well, and that is object oriented programming.

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Or Olby, in short, basically, we are going to apply all of our rules regarding variables, regarding

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collections, regarding methods, and we're going to build up some more topics on top of that, such

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as classes such as properties.

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And also we're going to go deeper into the methods topic.

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I think that this section is very important for everyone who wants to find a job as a programmer, because

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object oriented programming is very important for you to pass interviews or to build any program which

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is complex.

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We'll start off with basic three basic terms.

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I'm going to show you right away an example of visual example of how objects are built.

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And then we're going to start from the beginning and explain each term, as we always do.

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And the example that you will see in this lecture will start building it from the start from the next

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lecture.

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All right.

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So this is an introduction of video.

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And from the next lecture, we will start building it up from scratch.

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So.

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All right, let's begin.

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All right, then.

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So this will be the introduction of video.

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So let's start off explaining what is object oriented programming actually means.

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OK, so Python is an object oriented programming language.

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This we already know and it gives us unique abilities for flexible and useable code.

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OK, so let's see some introduction visualization in order to understand what is object oriented programming,

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we'll talk in general terms without getting into details.

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And later on, after we explain each of these terms deeply, we will build up this example from scratch.

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OK, so first of all, there is a new entity we're going to study, which is called the class.

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And that class wraps are methods which we already know, an additional entity, which is called properties.

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OK, so methods already familiar with methods, but properties are like a variable off that object.

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OK, we will later on go into details.

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Just remember that properties state for variables.

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OK, these are the variables of the object.

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So this is an introductory, introductory, introductory visualization.

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So a class basically is in reference to cause it's a general car sketch.

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OK.

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Our car our car has methods which is which are methods as we know them.

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For example, we have fuel calculator, we have check engine counters, we have door is open method.

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And all of these are methods.

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We can put calculations in them, math calculations or some other like manipulations upon variables

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that we want.

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All right.

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So methods are methods as always, while properties are a variable off that object.

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OK, so in properties we might have fuel status current km kilometers on engine or door status.

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All right.

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So this is a general car search, meaning each car that we want to produce from our factory will have

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all of these parameters in the in the car while it's being made.

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OK.

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And from here, let's scroll down a little bit.

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OK.

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So from this basic sketch, we can now create a new instance of an object, OK, instance of an object

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for a specific car model.

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While here we had general car sketch.

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Now from this we can create a specific car model using an instance of an object.

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We will obviously going to learn how to do it.

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You're not supposed to know.

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OK, and also we can you reuse methods endlessly for each car model.

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OK, so from this we're going to create several cars and each car would have all of these properties

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and methods, each one of them with its own properties and methods.

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OK, so for example, here we have first object.

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For instance, from the car sketch that we have seen here, OK, we want to create an object instance.

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OK, so from the sketch, we want to create an actual car, basically.

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So this time we have actual variables here, which are the properties, OK?

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Remember that properties are the same as variables.

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Later on, we'll show exactly what they are.

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So this Ford Focus Focus car has fuel status then current kimmet kilometers on engine are 240 and Dorje

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status is closed.

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OK, these are the variables that this car contains.

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All right.

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And at the bottom, we have the methods and fuel calculator.

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We have some kind of printout.

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You still have 10 liters of fuel, OK, after some calculation made there.

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We have we have a printout inside that method and we have a printout that says you still have 10 liters

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of fuel.

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Check engine also have some calculation.

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And at the end we have a printout.

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You need engine check in one thousand and 50 kilometers and there is open the same.

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All doors are closed.

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OK, there are some check up in here.

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Inside this method we check which checks if all doors are closed.

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OK, basically, for example, door is open.

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Check can receive the variable off the property of door state status.

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OK, so it can receive it and check what value it has here, this variable and accordingly then to print

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out whatever we want.

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OK, so these are the basics.

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And from the other hand, we have a second object instance, an Audi A3 and this time Fuel Staros is

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15 as opposed to here we had 10.

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OK, the values are different.

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So fuel status is twenty five current km on three hundred and ten dollars status is open.

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And this time the fuel calculation, the method, this method, the calculation here was different and

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it says you still have 25 liters of fuel.

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Engine check, you need engine checking, eight more kilometers and the door is open chag.

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Not all doors are closed.

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OK, so we have basically this sketch here.

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This is a sketch.

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It has certain methods and certain properties.

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OK, and then each car gets its own properties and its own values of properties right here.

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And we can make separate calculations for the methods as well for each car model.

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OK, so this is basically the main idea off objects.

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OK, the class that you were going to learn straightaway in the next lecture is like a sketch.

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And from that sketch, from that class, we can create an instance of an object, meaning we can create

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actual cars in our case and give its own properties and give its own values of properties here and use

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this these methods accordingly.

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For each of these cars.

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We're actually going to give this instance, this entity.

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We're going to give it actually a name, a Ford Focus.

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And inside this Ford Focus, we're going to insert some values inside.

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OK, this is as much visualized as I can do it.

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And don't worry, we're going to start all this from scratch.

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From the next lecture, we'll learn what our classes, what our methods in the terms of object oriented

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and also what our properties are.

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I think that concludes our introduction video.

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And I will see you in the next lecture.

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Thank you.