PHP-and-MySQL/C2/Variables-in-PHP/English

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Time Narration
0:00 Welcome to a basic tutorial on PHP variables.
0:04 Let me quickly go through a few things first.
0:07 PHP variables are very easy to use; I'm sure you'll understand them straight away.
0:14 You don't need to declare them and they're very easy to write.
0:18 You can add a value to a variable half way through the script.
0:23 Also, they automatically convert to the data type you require.
0:28 So there's no need to declare them in a different way each time, or create a value for them each time.
0:36 So, for example, let's create our PHP tags here and our content goes in between.
0:41 Okay. Now we start with the dollar sign and then we have our variable name.
0:47 Please note that you can't start with a "number". So I can't start with a '1'.
0:53 What I can start with is an "underscore" or a "letter".
0:57 No other special characters are allowed except underscores, letters and numbers, as long as it doesn't start with a number.
1:05 So that would be perfectly acceptable here.
1:09 Okay, so I'll create a variable called "name" and that's going to be equal to a string value contained within double quotes, just like we used for the "echo" function.
1:21 'My name is Alex'.
1:23 On the next line, we're going to create another variable using again a dollar sign, called 'age'. That's going to be equal to '19', without double quotes.
1:33 Now the reason for this is that this is an integer.
1:36 You can use it for decimal values as well. So this could be '19.5' or nineteen and a half.
1:43 That would also automatically convert this into a decimal.
1:48 However, at the moment it's just an integer. That's how I want it - the variable 'name' is a string and the variable 'age' is an integer.
1:57 So let's try echoing these out.
2:00 What we need is "echo" and the variable name, not forgetting your line terminator.
2:06 Okay, let's find our file named "variables".
2:11 Okay, "Alex" has been echoed out, just like I've said here, "echo name".
2:16 Let's try and echo out my age now.
2:19 It's just an integer variable and that's been echoed out here.
2:24 Okay so, the thing with variables is that they're very easy to concatenate into a string.
2:30 In fact, probably, concatenation is the wrong word – they're very easy to include inside your string.
2:36 If you don't know what concatenation is, it just means to join two things together or to join two strings together in a line.
2:46 So, an example of concatenation would be, let's see, 'concat' and then I could say, '.' and then 'ination'.
2:56 Now, this would echo out 'concatination'.
2:59 Let's try this. Okay?
3:03 But there is a completely different tutorial on that. So, what I'll say is, for now, you don't need to include this as one of your variables when you're echoing it out.
3:14 If you can't follow this, don't worry. This is very, very simple.
3:18 I'll say "My name is" name "and my age is" and put my age down.
3:24 So, it's all in one string, all in one echo, and we've just got 'My name is' – plain text.
3:32 Variable is called. This is put here. Then when age is called, the value for age is put here.
3:40 So, we can refresh that and you can see that "My name is Alex". That's our variable. "and my age is 19" and that's our variable.
3:48 So they're really easy to put into strings.
3:52 Okay, this is all you really need to know now about variables.
3:56 There are other types of variables, like boolean, decimal – which I've shown you, for example like '19.5'.
4:06 You would declare them in the same way, with a dollar sign.
4:10 So practice this and you can come back and learn some more advanced functionality later on, when I'm going through some other projects.
4:19 Thanks for watching! This is Joshua Mathew dubbing for the Spoken Tutorial project. (Script contributed by Bhavini Pant).

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Chandrika