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Hello and welcome to this video.

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In this video I will be introducing you to JavaScript variables what are variables in JavaScript javascript

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variables are containers for storing data values in order to create a variable you need to use the var

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key word which is spelled thi r he has to be in lowercase.

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Also when you create variables creating variable means declaring variables is the same P when you declare

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variables you have to assign a value to variables and you use the equal sign to assign values to a variable.

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For example if I wanted to create a variable X I'm going to give it a value of 7.

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Also if I want to create a variable called say my car and I give it a value of posh.

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When you are creating variables is always good practice to name your variables closely to what they

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are going to store the type of data they are going to store.

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Example I have named this variable my car which is an indication that the type of data I'm storing is

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relating to cars not is it to difference in the two values here.

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This one here the values 7 which is in number and note is here.

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The value here support and I've put quote around it when you are declaring variables.

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If you are declaring a text you have to enclose it in quotes.

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You either have to use single quotes or double quotes but you can't mix them you can't use a single

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quote here and then a double quote here.

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That's the only way the computer will understand that it is dealing with a text.

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You need to include the values in quotes.

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You don't need to do that with numbers because a computer knows that there is a number but if you want

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a computer to know that is a string they call it a string.

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In programming you want to know that this is a string.

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You need to include it in quotes.

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Also notice I've used semicolons here which is important.

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That indicates that that is the end of that statement.

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A javascript program is basically a collection of statement.

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This indicates this is one statement.

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These indicate this is another statement because of the semicolon.

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So you have to do that when you're declaring variables.

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You can also declare variables without assigning them a value.

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So when you declare a variable without a value it is known as on defined.

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Once you have defined or declared a variable you can change its value.

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For example you have already defined a variable called my car.

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If I wanted to change the value from posh for example to a range rover.

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All I need to do is call the variable by name and assign it a different value so that we already change

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changed value once you've declared a variable.

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You can change the value a variable that is declared without a value is known as on defined.

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Also it's very important to know that JavaScript is case sensitive.

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So for example here declared this variable.

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My car.

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Car with open case see if I tried to reference it with a lower case c it will not work.

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You can experiment with JavaScript inside your web browser console if you are using a Mac you can access

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to a web browser console by clicking on option command and J what you call the web browser open.

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If you are on a Windows based computer once you've got the web browser open you can just press F 12.

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That will give you the Web console.

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I've got the Google home page open so I'm going to access the web console just by hitting the F 12 on

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the keyboard and that will give me the console through this.

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This is the developer console where you can experiment with JavaScript so there are different ways you

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can docket.

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So if you click here at the moment is dock to the side.

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You can also dock it to the bottom and that will give you the page to web page you currently view and

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then you can expect with a code on the side or you can do it on this side dock it to the left.

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So depending on whatever you fancy you can take it wherever you like.

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I'm going to Joe's docket on the need for now.

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So let's try and experiment with some javascript so I'm gonna declare a variable inside the console

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here.

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Just type in VR to declare a variable and I'll give the variable a name of X give you the value of 7.

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So now if I want to call this variable all I need to do is call the variable by his name.

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If I press X it will return the value of 7.

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Now that I've declared the variable i can also change its value.

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All I need to do is call it by its name.

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Use the equals 2 and assign it a different value.

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Now if I call the variable x again in the longest 0 7 both in our stores 8.

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Same thing 5 declare another variable called let's declare a new variable.

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I'm gonna call this variable my car.

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Okay

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my car.

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Okay you know I'll give you my car and I'm gonna give it a value of see Pausch.

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Okay.

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And I need a semicolon to end that.

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So now if I call these variable by its name if I say for example if I call call it by car.

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It will not work.

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You know why.

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Because I've referenced it in lowercase.

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You know the C I use this an uppercase.

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So it's very important that you reference two variables the way you've defined them.

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If I now go back and call it again with uppercase C it should return the right.

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You can see it's giving me the value of posh.

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Once you've declared a variable you can easily change its name change its value.

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So if I want to change that to something else I'll just call it by name.

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So I want to change this to a Ford for example.

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All right.

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And to a semicolon.

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Now that's changed.

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If I call the variable again by name it will no longer store render right.

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Will be now storing Ford.

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So these are some of the basic examples you can use to play around in the pros and cons of the console

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is very useful for playing around with little little look to values like this.

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So you can experiment and get acquainted.

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So that's it for this video on javascript variables.

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Many thanks and bye for now.