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We've seen a little bit of why Object Oriented Programming is really useful,

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but now let's take a look at how you would actually go about implementing Object

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Oriented Programming.

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So in the last lesson we talked of this example of the restaurant,

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where we hired three types of staff,

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and we had a manager who would then manage all of these three different types of

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staff. Now,

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the reason why Object Oriented Programming is called that is because it's trying

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to model a real world object.

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So let's say that we are creating a virtual restaurant. Well, in this case,

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we probably have to model a virtual chef, waiter,

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cleaner, and manager.

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So let's say that we were going to model a waiter. In order to model our waiter,

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there's probably two things we need to think about: what it has and what it does.

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In terms of what it has, well, it might have variables like,

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is it holding a plate, true or false?

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Or which tables is it responsible for? Maybe table 4, 5 and 6.

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Now it also has things that it does.

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Maybe they're able to take an order to the chef and maybe they also need to take

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payments and add money to the restaurant. So these two different things,

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what the waiter has and what the waiter does are

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the two most important things that make up an object: its attributes and its

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methods. By looking at the code,

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you can pretty much see that the attributes is basically a variable.

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An attribute is just a fancy word for a variable that's associated with a

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modeled object like our waiter here.

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Because it's not just a free floating bit of a variable, right?

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It's not just somewhere in our main.py.

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It's actually a variable that's attached to a particular object.

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It's the waiter's tables responsible.

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Now the method goes along the same vein. These,

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as you can clearly see, are just functions

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but we call it a method because it's a function that a particular modeled

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object can do.

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We need a waiter object to take the order and we need a waiter object to take

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payment. Again, these are not just free-floating functions.

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Now, there's a lot of new words that are part of Object Oriented Programming and

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programming in general, we're going to see them again and again,

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and eventually it's going to become a word that's going to be in your

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dictionary. But for now, just remember that in Object Oriented

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Programming,

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we're trying to model real-life objects and those objects have things

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and they also can do things.

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The things that they have are their attributes

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and these are usually modeled with variables, and the things that they can do

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are called methods and they are modeled by functions.

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So essentially, an object is just a way of combining some piece of data and some

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functionality altogether in the same thing.

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But we can actually have multiple objects generated from the same type.

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So when we've modeled a particular job in our virtual restaurant

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like the waiter's job,

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and we figured out what are the things that the waiter have and what are the

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things that it can do, well,

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we can actually generate multiple versions of the same object. So we could have

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Henry who's a waiter and we can also have Betty who's a waiter,

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and we can generate as many of these as we want from the same blueprint.

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And in OOP we call this blueprint, or this type, a class.

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And we call these individual objects that are generated from the blueprint

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an object.

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So now let's take a look at how you use these class blueprints to create an actual

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object.