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Hello and welcome.

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In this video I will introduce you to some javascript data types in programming in general and also

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in JavaScript the data types basically refers to the classification that specifies the type of value

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that a variable has or stores.

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There are different types of data types in JavaScript.

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Here's a basic table with some basic javascript data types.

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So I'm going to start with the top one which is this string.

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This trend basically is a sequence of text that must be enclosed in quotes.

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You can use either single quotes or double quotes but you cannot mix the quotes.

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For example here you can declare a variable called my data and set it to this value.

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You can see I've got quotes around it.

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I've got my web console open so the way to access your WAP web console if you are on a Windows computer

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open up just Google home page and type in control shift and Jay on your keyboard o f 12 and that would

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give you access to the Web console if you are on a Mac you do command shift and J that would give you

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access to the console.

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So let's create a simple variable that will store a string data type so in my console.

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I'm going to create a new variable by typing in the keyword V A r and I'm going to call this variable

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my colors okay.

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And I'm going to give it a value gonna give this value or read.

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So that's a value you can see I've enclosed the value in quotes which means if a string data type A

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computer will recognize that as a string data type.

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So if I want to reference this variable all I need to do is call it by its name and age or just return

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the value read.

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So that's a simple example of how a string data type can be used.

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The next data type I want to mention is the number data type basically refers to any numerical value.

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And it does not need to have a quote around its value to let me illustrate by creating a simple variable

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or store in no data type.

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So I declare a simple variable by typing in the keyword var and I'll call this variable door

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Don number and I'll give it a value of 7.

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So this is known as a no data type.

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You can see it doesn't need ports around it.

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So if I want to reference that variable I just call it by its name Don number and it will return the

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value of seven the next data type.

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I want to mention it's called a boolean a boolean basically represents two values that one can be true.

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The other can be false and we're using boolean values no quotes required to illustrate a billion of

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value.

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I'm just going to compare two values.

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I'm going to say four is greater than three.

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That will return true and a five say three is greater than four.

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And that will return false.

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So that's basically how boolean value data types work the next day to type.

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I want to mention is called an array an array is a data structure that stores multiple values as one

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single reference.

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Basically what that means a variable can store only one value but with an array you can store multiple

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values as one single reference.

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You can see here I've got two values here.

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Ford and Toyota both I'm referencing it on the one variable called my cars.

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So let me show you a quick illustration.

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Inside the console someone should declare a variable called my cars

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and I'm going to set it to a course to and this is how you declare an array with square brackets and

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inside the square brackets is where you place the values.

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So let's say the first value I say it's a Ford and second value I say is a Toyota.

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When you are using a raise you separate each of the values with a comma.

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The only way you don't need a comma is the very last value.

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So this basically here is an array and the way you access the values in an array is via the index.

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So the way an array is for France is by the index.

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So this will be known as zero index.

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This will be one if you have several.

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You can have as many as possible inside the square brackets but you need to separate the values with

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a comma.

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And if they are on the string data type you enclose it in quotes.

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If they are not then you don't need to enclose it in quotes.

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So for example if I wanted to access value.

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Number one this is zero index zero which is Ford Hall I need to do is typing my cards

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and in lowercase type in my cars and then in square brackets.

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I type in value zero which will represent the index I'm trying to target and that should return.

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You can see it has returned Ford.

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So that's how you.

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If I had like 20 inside here I will reference it fiber index based Val number.

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So Ford the very first values that zero index to hit I would be index number one and so on so that's

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how you access the values in an array.

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So the key difference between an array and variable is that an array can store multiple values as one

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value.

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If you see here I got just got this variable called my colors and is only stored one value here I've

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got a variable called my car's only stores multiple values by reference as a single values core my car's

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next data type I want to quickly mention it's called the object everything in Javascript is basically

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an object.

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So all the examples I have shown so far they are basically objects can also represent JavaScript objects

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with curly braces as I've done here I've declared a variable called Person set the value to cause to

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the first name got John last name though so you can represent an object like this way as well but by

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using curly braces.

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So if I wanted to access this object here all I need to do is call the variable by its name and it will

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return the.

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You can see he's returned the first name as John last name as do another data type.

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I want to introduce you to court.

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No you may come across this in your learning with JavaScript and basically in no data type is something

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that does not exist.

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You can also use the normal data type to empty the value of a variable and a normal is also an Object

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data type so you can see here got a variable here called Door Number and with a value of 7 so I can

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empty that value by just typing in the name of the variable which is number and set in the value to

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know and that will empty the current data it stores if I call these variable codon door number now it

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will come back saying no because I've emptied out the whatever it was storing.

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Okay.

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So a null data type means basically nothing.

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He doesn't store anything doesn't lock in in the final data type.

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I want to talk about is called undefined undefined is similar to No.

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The only difference is that the different data type on defined is undefined while in no data type is

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also an object data type or if you declare a variable you don't give it a value that will become undefined.

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For example if I call me and say variable suites

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and I don't give it any value.

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That would become undefined if I tried to call it by its name.

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It would come back undefined.

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So that's a key difference key difference between a normal and undefined.

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Is that undefined is not an object data type.

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While normal is an object data type so that's basically it for this video on javascript data types.

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Thanks for watching.

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Bye for now.