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Welcome back everybody.

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All right so I'm just going to go ahead and actually get rid of this second paragraph tag right here.

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It's pretty simple and I'll just go ahead and get rid of that too here so and we'll test everything

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and everything still works OK.

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Now in this Tauriel what I'm going to do is I'm going to talk to you about something called the variables.

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Now I've told you that the function is like a box of code and that box of code will do something.

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But if you can imagine a box a code with a whole bunch of other boxes that hold certain values.

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OK.

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And these values don't necessarily run code.

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All they do is they're like numbers and names or something like that.

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OK.

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Now variables are really important and there are like a box of information really so you have the function

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which is a box that does something and the variable is the box of information and variables are super

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important because they can again be names they can be numbers or they can be a whole bunch of different

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types of data.

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Essentially what it is.

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Right.

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So first thing we're going to do in order to actually call the variable.

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All we need to do is type in var OK.

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And this var here is the center for variable and javascript's actually unique in that you don't have

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to specify the type of variable.

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So there's different kinds of variables.

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There is something called a boolean variable which is true or false.

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There's a integer variable which is numbers and their string variables which is character.

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So if you want to make a string variable.

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For example it would be like my name.

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You can say your name anybody's name but what you couldn't do is you couldn't put a name inside an integer

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variable or an int variable because integers are the only numbers.

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There's no characters allowed and you couldn't put a number inside a boolean variable cause a booleans

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will end true or false.

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Now all we have to do in javascript is call the name so we can type in variable name just like this.

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And there we go.

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So now we have a variable that's all it is and we can have hundreds of these variables in fact if you're

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making games or apps you generally have a lot of variables with with your program here and that's one

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thing when you're learning about programming.

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You see examples with two three four and maybe on the outside chance 10 variables.

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But when you're actually developing you actually use quite a bit and especially when you're releasing

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because you do have to you really have to add it in a bunch of data for pretty much a lot of things

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that happened within the program.

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So we have a variable name just like that.

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So what we can do is we can go to Web site in variable number k and we'll type this again.

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We call this variable name and you see him putting semi-colons at the end of this.

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And there you go.

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So the thing is is that these variables are the same thing.

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Right now they're just variables they're just boxes.

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Even will sign colors to these boxes.

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OK.

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So these are both a blank cardboard colored box.

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OK.

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But as soon as we do this and it's called initialising variables we type in equals zero.

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Now what we've done is we've changed this variable from being a a string variable or just a blank variable

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to an integer variable.

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Now again javascript's since it doesn't really distinguish between strings and ense like other languages

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do.

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We can actually mash these together.

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But for the most part to avoid errors you want to think of variable number as always going to be a number

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is never going to be a string.

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And in fact it's much better if you think this way because it will cause a lot of hard hardships down

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the road.

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Now let's go into variable name here.

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So what we need to do is you need to put in two quotes like this and we're going to type in your name.

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There we go.

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Pretty simple right.

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OK.

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Now let's just do something cool here.

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What we're going to do is we're going to go alert and watch this.

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We're going to type in variable number just like that.

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OK.

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There we go.

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Two warnings and if you change the text you see that it comes out to zero.

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And if we type in variable name just like this James the it comes out as my name.

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OK.

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So if we change this to whatever we want let's say too and we change it back to variable number.

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All right change the text and it comes out too.

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So what it is is that this alert and whenever you see this any kind of any kind of brackets it means

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you can put something in there.

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OK.

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So this alert here we typed in.

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You know we typed in a string here OK and it came out as pop but we can also put in any kind of variable

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we wanted to that and you'll also notice that there is a bracket here and that's for something really

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different.

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OK that's for something that's what you can put put variables into a function and they can do stuff.

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But we don't really need to worry about that quite yet.

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What I do want to show you is that you can actually go and put in variables wherever you want here.

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Now watch this if we want to change the text to a variable name just like this.

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We change the text and you can see that this is undefined here and the reason is is that I didn't put

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anything there.

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So let's just go ahead and put in a pop here.

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OK.

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And you'll also notice that when we do this here pop it does change to variable name.

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OK so I'll just go ahead and delete this here and you'll see here that if I just expand this out a bit

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it will be a little bit easier to look at.

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So what you'll see is you see the document or get an idea paragraph text.

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It's TMail equals two.

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The variable name or we can make it even two variable number k just like that.

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And if we change the text it changes too.

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OK.

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And so that's essentially what.

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That's essentially how you use variables.

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Again variables are really important because they can take in anything for example if you're making

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a calculator app you can take in the variable that was typed in and then added to something which I'll

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show you in the next tutorial.

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I'll see you guys next time.