WEBVTT 0 00:00.540 --> 00:04.530 The objective is we want to be able to build a turtle race, 1 00:04.860 --> 00:09.860 where we have multiple turtles to run along a line and then see who actually 2 00:10.860 --> 00:14.400 reaches the finish line first. Now here's a question though. 3 00:14.970 --> 00:18.660 We know how to build one turtle from the turtle blueprint, 4 00:18.930 --> 00:23.130 but what if we need more turtles? How do we get hold of them? 5 00:23.490 --> 00:24.210 Well, 6 00:24.210 --> 00:29.210 we know that we can use a class or a blueprint to define what a turtle should 7 00:31.950 --> 00:34.350 appear like and how it should behave. 8 00:34.710 --> 00:37.830 So what it has and what it can do. Now, 9 00:37.830 --> 00:42.830 we can then take this class and construct an actual turtle object from it 10 00:43.470 --> 00:46.980 which is then doing all the drawing and walking around on the screen. 11 00:47.430 --> 00:51.900 So this is what the code has looked like so far. We have Timmy 12 00:51.960 --> 00:56.960 which is our turtle object, and turtle coming from the turtle module is the 13 00:57.330 --> 01:00.060 class which is used to construct this object. 14 01:00.420 --> 01:05.420 But that's not the end of the story because the whole reason why we can have 15 01:06.120 --> 01:10.440 these blueprints is so we can make more objects. 16 01:10.830 --> 01:15.060 So, we're not limited to just one turtle object. 17 01:15.090 --> 01:19.980 We can create as many as we need in the same way that we have created Timmy. 18 01:20.220 --> 01:23.910 We create Tommy, Johnny, Jenny, and Benny. 19 01:24.840 --> 01:28.890 Even though both Timmy and Tommy are turtle objects, 20 01:29.130 --> 01:32.610 they actually function completely independent of each other. 21 01:32.940 --> 01:37.920 So in programming, we would say that they are each a separate instance. 22 01:38.100 --> 01:39.750 So what does that mean? Well, 23 01:39.750 --> 01:43.830 that means that they're each an example of the turtle object. 24 01:44.160 --> 01:48.810 So just as you and I are both examples of human objects, 25 01:48.930 --> 01:52.140 Timmy and Tommy are both examples of turtle objects. 26 01:52.650 --> 01:55.020 And that means that at any moment in time, 27 01:55.140 --> 01:59.070 they could have different attributes and they could be doing different things. 28 01:59.730 --> 02:01.260 So that means, for example, 29 02:01.290 --> 02:06.290 Timmy could have his color set to green while Tommy could have its color set to 30 02:06.960 --> 02:09.360 something completely different, like purple. 31 02:09.750 --> 02:14.750 Now the fact that each of these objects can have different attributes and can be 32 02:16.050 --> 02:21.050 performing different methods at any one time in programming is known as their 33 02:21.660 --> 02:22.493 state. 34 02:23.070 --> 02:28.070 So the state of Timmy's color attribute is green and Tommy's color attribute is 35 02:29.370 --> 02:31.260 purple. So in this case, 36 02:31.290 --> 02:35.970 they have different state in terms of their attribute or their appearance. 37 02:36.510 --> 02:39.780 But they can also have different state in terms of whether 38 02:39.780 --> 02:42.780 if they are doing something. For example, 39 02:42.810 --> 02:47.810 Timmy could be asked to move forwards while Tommy is staying completely 40 02:48.750 --> 02:51.900 stationary. So Timmy is in the middle of a method call 41 02:51.930 --> 02:56.340 whereas Tommy is not doing anything at all. Now in the next lesson, 42 02:56.370 --> 02:59.200 we're going to be building out our turtle racing game 43 02:59.620 --> 03:01.360 and we're going to see this in action. 44 03:01.540 --> 03:06.540 The idea that you could have separate versions of the same object each with a 45 03:07.480 --> 03:12.480 different state and acting completely independently from each other in order to 46 03:13.600 --> 03:17.560 race against each other. So don't worry if this doesn't make sense 47 03:17.560 --> 03:20.440 a hundred percent just yet. Head over to the next lesson 48 03:20.740 --> 03:24.190 and we're going to start writing some real code to better understand this 49 03:24.190 --> 03:24.850 concept.