WEBVTT 00:00.590 --> 00:04.040 I will call you back again to another video lecture in PHP. 00:04.370 --> 00:09.380 In this video lecture we go ahead and look at the variables in PHP. 00:16.160 --> 00:21.650 So right on my screen I have a little story I just made for us. 00:21.650 --> 00:30.260 And this says once upon a time in the land of Alaska, there was a man named Peter who is 80 years old. 00:30.620 --> 00:33.590 Peter lived in Alaska for 80 years. 00:33.620 --> 00:38.630 One day Peter left Alaska and never returned again. 00:38.810 --> 00:44.270 So this is a piece of story, a formalized story that we have right in here. 00:44.300 --> 00:49.730 So this can be a novel, maybe up to 100 pages, 200 or 300 pages. 00:49.730 --> 00:59.210 And in that novel, you might have a Alaska name like up to 100 times, and you have the name Peter 00:59.210 --> 01:07.190 Are occurring about 200 times, and these may occur as many times as possible. 01:07.220 --> 01:11.360 Then, if we go ahead and run this graph, let's go ahead and save. 01:11.360 --> 01:12.650 These are the. 01:12.680 --> 01:13.460 Check it out. 01:13.460 --> 01:14.930 So it says on a. 01:15.260 --> 01:21.140 Once upon a time in the land of Alaska, there was a man named Peter who is 80 years. 01:21.170 --> 01:21.770 All right. 01:21.770 --> 01:22.820 I think this is so big. 01:22.850 --> 01:24.350 I'll go ahead and I'll reduce this. 01:24.350 --> 01:27.230 And now everything is now alright. 01:27.230 --> 01:33.080 So once upon a time, in the land of Alaska, there was a man named Peter who is 80 years old. 01:33.260 --> 01:35.510 Peter lived in Alaska for 80 years. 01:35.540 --> 01:38.960 One day Peter left Alaska and never returned again. 01:38.960 --> 01:43.580 So you can see in this story I can do to change anything. 01:43.730 --> 01:51.890 Let me say I'm the editor who is editing this book, and I want to change the name Alaska to maybe anything. 01:51.920 --> 01:55.010 Maybe I can name that to be, or here or any other thing. 01:55.010 --> 01:59.260 So I'll go ahead and start changing this one by one. 01:59.260 --> 02:00.820 So I'll go right in here. 02:00.850 --> 02:03.760 I change this and I come over here. 02:04.030 --> 02:06.820 I change this as well. 02:07.630 --> 02:10.090 Then the next place is the last one. 02:10.120 --> 02:11.530 I will change this again. 02:11.530 --> 02:16.960 So if I go ahead and save this or run this code, you can see that Alaska has been changed. 02:16.960 --> 02:19.270 And now we have Ohio right in here. 02:19.510 --> 02:25.630 So the state has changed from this to once upon a time in the land of oo. 02:25.660 --> 02:30.190 That was a man named Paul and no longer Peter, who is 80 years old. 02:30.310 --> 02:32.950 Paul lived in Ohio for 80 years. 02:32.980 --> 02:36.160 One day Paul left Ohio and never returned again. 02:36.160 --> 02:38.410 Maybe Paul is dead or Paul has relocated. 02:38.440 --> 02:39.760 What is 80 years? 02:39.760 --> 02:41.410 So this is just a story. 02:41.410 --> 02:45.370 And you can see I am changing the names one by one. 02:45.370 --> 02:49.540 So this is easier for if four lines of code I can actually do that. 02:49.570 --> 02:53.770 Or what if this is a whole novel and you want to do this? 02:53.770 --> 02:58.030 So how do you start changing this one by one without making a mistake. 02:58.060 --> 03:03.520 There must be a time, or you might miss some steps, or you might miss on names. 03:03.520 --> 03:07.270 Or you might write something that is not just what is supposed to be. 03:07.300 --> 03:09.130 Maybe there is a typo somewhere. 03:09.130 --> 03:11.020 So how can you be able to do this? 03:11.050 --> 03:15.280 You know, how can you change this with just a line of code? 03:15.760 --> 03:18.850 So let me go ahead and introduce us to what variables are. 03:18.880 --> 03:27.910 So variables are a containers that contain a particular piece or a word that you want to use any place 03:27.940 --> 03:29.080 in your code. 03:29.110 --> 03:38.170 So anytime you want to change a son, a name or a number or a decimal number or an integer variable, 03:38.200 --> 03:41.200 anything, you can actually use variable to do that. 03:41.200 --> 03:45.490 Now I'll go ahead and show us how to do that because it's just a container. 03:45.490 --> 03:48.880 And now it's actually learn by doing so. 03:48.910 --> 03:58.720 In order to write a variable in Python what we need to do is we go ahead and use the dollar sign. 03:58.750 --> 04:05.830 So this dollar sign is what is going to help us to be able to declare a variable. 04:05.860 --> 04:08.860 So once you create a name or that symbol. 04:08.890 --> 04:13.300 Dollar sign, it means that the next thing that comes is a variable. 04:13.330 --> 04:14.800 Now let's go ahead and see. 04:14.950 --> 04:17.950 This is a story. 04:17.980 --> 04:19.480 Now we call the story. 04:19.510 --> 04:22.810 Town is a town where you want to change. 04:22.810 --> 04:23.410 Let me see. 04:23.440 --> 04:28.060 I want to name this town, um, or camcorder to be. 04:29.260 --> 04:33.850 Um, let me call that to be any name town. 04:34.690 --> 04:37.840 So the town name is now Newton. 04:37.840 --> 04:41.680 And I can also go ahead and change the name. 04:41.800 --> 04:46.870 Now, how do I change the story name? 04:46.900 --> 04:48.280 Let me call out to the story name. 04:48.280 --> 04:49.450 You can call it anything. 04:49.450 --> 04:55.510 It's just a variable is a container that holds, um, a piece of information which can be able to use 04:55.510 --> 04:56.410 any place. 04:56.440 --> 04:56.830 All right. 04:56.860 --> 05:01.930 So I name the first one the town story town, the name I call it to be story. 05:02.110 --> 05:02.890 You can name it. 05:02.920 --> 05:04.720 You can give it any name you want. 05:04.750 --> 05:05.140 All right. 05:05.170 --> 05:06.310 It mustn't be story name. 05:06.340 --> 05:10.600 Now I'm going to change that to be the record out to be George. 05:10.630 --> 05:17.230 Then I will go ahead and give the last one to reach. 05:17.260 --> 05:17.800 All right. 05:17.800 --> 05:22.870 So I can change the age to be 95. 05:22.900 --> 05:23.230 All right. 05:23.260 --> 05:24.580 Put a semicolon at the end. 05:24.610 --> 05:32.950 Now, you can see that when I was giving this, I call this I give a this inside a quotation mark. 05:32.950 --> 05:34.330 Because this is a string. 05:34.330 --> 05:39.640 We have not discussed strings and we have not talked anything about integers and strings. 05:39.640 --> 05:40.870 But this is a string. 05:40.870 --> 05:44.320 That is why it is inside a double quotation mark. 05:44.320 --> 05:46.540 So what does an integer. 05:46.570 --> 05:47.860 You don't need that. 05:47.890 --> 05:49.720 You just leave it the way it is. 05:49.750 --> 05:51.940 Okay, now let's go ahead and save this. 05:52.240 --> 06:02.130 So the next thing I have to do is I'll go to Ohio and I'm going to change this to story and let me see. 06:04.440 --> 06:06.000 Story town. 06:08.880 --> 06:09.360 All right. 06:09.390 --> 06:11.280 So story town, let me go ahead and save this. 06:11.280 --> 06:13.170 And we're going to run this code and check it out. 06:13.200 --> 06:19.590 Now you can see once upon a time in the land of Luton and no longer Ohio, what happens? 06:20.310 --> 06:27.510 Even though I did add a little right in here, what actually happens is that the variable name has been 06:27.510 --> 06:31.770 stored inside this variable container named Story Town. 06:31.770 --> 06:37.620 And any time or any place you see Story Town, what is going to be there is Luton. 06:37.620 --> 06:46.890 So if you change this Luton to anything, let me say if you call out to be Manchester, so let's call 06:46.890 --> 06:49.770 it out to be Manchester and let's go ahead and run. 06:49.770 --> 06:54.240 This is considered in the land of Manchester so it can actually change. 06:54.240 --> 06:57.450 So it's just a container that is holding a piece of information. 06:57.450 --> 07:00.840 So whatever you put inside there is what is going to be displayed. 07:00.870 --> 07:03.780 Now I'll go ahead and copy this. 07:03.810 --> 07:05.130 Let's go ahead and copy this. 07:05.370 --> 07:07.350 And then we go over here. 07:07.350 --> 07:12.690 Any place you see or hear we change that with this variable name. 07:12.690 --> 07:17.040 And I'll go ahead and change this as well. 07:17.640 --> 07:19.440 So go ahead and change this as well. 07:20.970 --> 07:22.260 Are we okay. 07:22.290 --> 07:23.790 I actually copied that. 07:23.820 --> 07:25.440 Let me go ahead and copy this again. 07:25.980 --> 07:26.460 All right. 07:26.460 --> 07:28.380 So I'll go ahead and paste this here. 07:28.380 --> 07:33.360 And then the story name is the name of the individual. 07:33.360 --> 07:38.460 So change this to story Name and change this to Store name. 07:38.460 --> 07:45.420 And wherever we see both with the story and then the Stone age, we got it on copyright. 07:46.470 --> 07:50.370 So let's go back to Etsy and we change this. 07:50.400 --> 07:52.740 and we also change this. 07:52.770 --> 07:56.610 Now we can actually save this and then go back. 07:56.760 --> 07:58.860 Go back here and run this code and check it out. 07:58.890 --> 08:06.270 So once upon a time in the land of Manchester, there was a man named George who is 95 years old. 08:06.300 --> 08:09.870 George lived in Manchester for 95 years. 08:09.900 --> 08:14.880 One day George left Manchester and never returned again. 08:14.910 --> 08:18.660 So you can see that we are able to change everything right in here. 08:18.660 --> 08:27.840 So if this story is like up to, um, 100 lines of code, we can actually go back here and go back to 08:27.870 --> 08:31.560 here and say Manchester, go back to Alaska. 08:33.630 --> 08:35.970 Let's go back to Alaska. 08:35.970 --> 08:43.020 And, uh, the name go back to Peter and the age go back to 80. 08:43.050 --> 08:46.050 Let's save this and run this code again. 08:46.050 --> 08:51.920 So once upon a time, in the land of Alaska, there That was a man named Peter who is 80 years old. 08:51.950 --> 08:54.020 Peter lived in Alaska for 80 years. 08:54.050 --> 08:56.540 One day, Peter left Alaska and never returned again. 08:56.540 --> 09:03.470 So we can see that we were able to use variables to be able to do all this without going back right 09:03.470 --> 09:06.620 inside the stories to modify that one by one. 09:06.650 --> 09:09.320 So that is one cool effect. 09:09.320 --> 09:11.690 And one thing good about PHP. 09:11.690 --> 09:17.330 So PHP actually knows when you are using a variable and it will automatically obey that. 09:17.360 --> 09:21.740 Okay, so whatever it is inside the variable, it actually gives you back to you. 09:21.740 --> 09:26.720 Because variable is just a container that we use to hold some piece of information. 09:27.230 --> 09:28.310 So that is cool. 09:28.340 --> 09:28.670 All right. 09:28.700 --> 09:31.880 So go ahead and practice with this. 09:31.910 --> 09:32.510 Check it out. 09:32.510 --> 09:35.600 And if you have any questions on anywhere it just let me know. 09:35.600 --> 09:37.730 And I'm going to get back to you as soon as possible. 09:37.760 --> 09:38.180 All right. 09:38.180 --> 09:39.710 So I want us to move together. 09:39.710 --> 09:44.630 And for any reason you have any problem, please don't forget to use the question and answer section. 09:44.630 --> 09:46.160 And I'm always going to get back to you. 09:46.160 --> 09:48.800 So thank you and see you in the next video lecture.