WEBVTT 0 00:00.060 --> 00:04.620 We've seen a little bit of why Object Oriented Programming is really useful, 1 00:04.980 --> 00:09.510 but now let's take a look at how you would actually go about implementing Object 2 00:09.510 --> 00:10.530 Oriented Programming. 3 00:11.370 --> 00:15.240 So in the last lesson we talked of this example of the restaurant, 4 00:15.750 --> 00:18.600 where we hired three types of staff, 5 00:19.020 --> 00:24.020 and we had a manager who would then manage all of these three different types of 6 00:24.300 --> 00:25.830 staff. Now, 7 00:26.160 --> 00:31.160 the reason why Object Oriented Programming is called that is because it's trying 8 00:31.410 --> 00:34.350 to model a real world object. 9 00:34.770 --> 00:39.570 So let's say that we are creating a virtual restaurant. Well, in this case, 10 00:39.570 --> 00:43.320 we probably have to model a virtual chef, waiter, 11 00:43.350 --> 00:44.760 cleaner, and manager. 12 00:45.270 --> 00:50.270 So let's say that we were going to model a waiter. In order to model our waiter, 13 00:50.910 --> 00:55.910 there's probably two things we need to think about: what it has and what it does. 14 00:56.790 --> 01:00.540 In terms of what it has, well, it might have variables like, 15 01:00.570 --> 01:02.790 is it holding a plate, true or false? 16 01:03.360 --> 01:08.360 Or which tables is it responsible for? Maybe table 4, 5 and 6. 17 01:09.510 --> 01:11.940 Now it also has things that it does. 18 01:12.390 --> 01:17.390 Maybe they're able to take an order to the chef and maybe they also need to take 19 01:17.670 --> 01:22.470 payments and add money to the restaurant. So these two different things, 20 01:22.500 --> 01:25.650 what the waiter has and what the waiter does are 21 01:25.650 --> 01:30.650 the two most important things that make up an object: its attributes and its 22 01:32.520 --> 01:34.980 methods. By looking at the code, 23 01:35.010 --> 01:39.750 you can pretty much see that the attributes is basically a variable. 24 01:40.260 --> 01:45.260 An attribute is just a fancy word for a variable that's associated with a 25 01:46.410 --> 01:48.660 modeled object like our waiter here. 26 01:49.260 --> 01:52.500 Because it's not just a free floating bit of a variable, right? 27 01:52.500 --> 01:54.690 It's not just somewhere in our main.py. 28 01:55.050 --> 01:59.130 It's actually a variable that's attached to a particular object. 29 01:59.400 --> 02:02.130 It's the waiter's tables responsible. 30 02:02.850 --> 02:05.970 Now the method goes along the same vein. These, 31 02:06.060 --> 02:08.520 as you can clearly see, are just functions 32 02:09.090 --> 02:14.090 but we call it a method because it's a function that a particular modeled 33 02:14.730 --> 02:16.500 object can do. 34 02:17.160 --> 02:22.160 We need a waiter object to take the order and we need a waiter object to take 35 02:22.260 --> 02:25.950 payment. Again, these are not just free-floating functions. 36 02:26.520 --> 02:31.520 Now, there's a lot of new words that are part of Object Oriented Programming and 37 02:31.740 --> 02:35.160 programming in general, we're going to see them again and again, 38 02:35.220 --> 02:38.160 and eventually it's going to become a word that's going to be in your 39 02:38.160 --> 02:42.720 dictionary. But for now, just remember that in Object Oriented 40 02:42.720 --> 02:43.350 Programming, 41 02:43.350 --> 02:48.350 we're trying to model real-life objects and those objects have things 42 02:49.590 --> 02:51.720 and they also can do things. 43 02:52.110 --> 02:54.780 The things that they have are their attributes 44 02:55.200 --> 02:59.980 and these are usually modeled with variables, and the things that they can do 45 03:00.280 --> 03:03.400 are called methods and they are modeled by functions. 46 03:04.060 --> 03:09.060 So essentially, an object is just a way of combining some piece of data and some 47 03:10.810 --> 03:14.170 functionality altogether in the same thing. 48 03:15.370 --> 03:20.370 But we can actually have multiple objects generated from the same type. 49 03:21.190 --> 03:24.940 So when we've modeled a particular job in our virtual restaurant 50 03:25.030 --> 03:26.800 like the waiter's job, 51 03:27.490 --> 03:31.090 and we figured out what are the things that the waiter have and what are the 52 03:31.090 --> 03:33.220 things that it can do, well, 53 03:33.220 --> 03:38.220 we can actually generate multiple versions of the same object. So we could have 54 03:38.950 --> 03:43.270 Henry who's a waiter and we can also have Betty who's a waiter, 55 03:43.840 --> 03:48.460 and we can generate as many of these as we want from the same blueprint. 56 03:48.970 --> 03:53.970 And in OOP we call this blueprint, or this type, a class. 57 03:56.170 --> 04:01.170 And we call these individual objects that are generated from the blueprint 58 04:01.480 --> 04:02.320 an object. 59 04:03.070 --> 04:08.070 So now let's take a look at how you use these class blueprints to create an actual 60 04:08.380 --> 04:08.950 object.