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Before we talk about the couple of ways of assigning values to variables, let's revisit the data types

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by exploring each of these types with code.

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So back to Visual Studio code over here.

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We are going to start with the primitive data types and it's going to be as this and I want to change

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the color to red.

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An example of the primitive data type, as we spoke about, is called string.

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And this is how it goes to declare a variable with a string value.

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It goes like this, like I said, that we are going to stick to const and let without using var.

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So for this I will say let full name is equal to John Doe.

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And as you can see, the way I'm naming my variables and we have a couple of ways to name variables,

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don't worry, we have a section to talk about the best practices or naming conventions.

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But for the meantime, just type the way I'm doing it.

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But the key note here is that your variable name must not have space in it.

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Again, we have a video to talk about the best way to declare variables.

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For the meantime, just follow along the way.

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As you can see, we have store a value of string inside full name and this is a string simply because

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we are using quotes around it and you can use double quotes or single quotes around it and it is the

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same.

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So if I go ahead and console log the full name, we're going to see John Doe inside the console.

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And as you can see, we have John Doe over here.

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So this is how a string.

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Then the next type of data is called the number.

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And we can declare a variable, for example, account number or account balance.

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So let me say account balance.

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Is equal to, let's say, 200.

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So I'm saving a number into a variable.

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So if I console log the account balance, we are going to see the 200.

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Save it.

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And there we go.

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We have 200 and I can access the account balance as that and I can also access the full name because

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now we have saved these values inside the internal memory of JavaScript.

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The next type of data is called Boolean, as we have spoke about, and this one holds only two values,

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whether true or false.

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So here I can say let is married.

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Meaning are you married?

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Then it can be false or true.

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So if I make it a false meaning, you are not married.

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All right.

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So if you check inside the console and I set four is married.

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As you can see, we have a value of false.

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Then the next type of data is called null.

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And it goes like this.

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Let me add a comment by saying.

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Let.

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Pending transaction is equal to null.

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Save it.

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And if you check inside the browser by searching for pending transaction, as you can see, we have

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value of Null and the next type is called undefined and I can declare a variable as country and is equal

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to undefined.

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So what is the differences between undefined and narrow, both null and undefined?

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In JavaScript they represent absence of value, but they are used in slightly different circumstances.

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For example, for undefined, it is a variable that has been declared, but it has not been assigned

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a value and by default it will give you undefined.

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And now, on the other hand is an assigned value, meaning it can be assigned to a variable that represents

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no value or no object, and it implies an empty or nonexistent value.

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So at this point, take it that they are all absence of values when a variable is being declared, but

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they have some differences in some situations.

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The next type of data type is called the symbol.

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So our other comment here by saying symbol and this is a new feature and we are not going to use this

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one in this course.

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But let me show you.

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I will say let unique.

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ID equal to symbol, bring the uppercase symbol and then pass in the ID, something like this.

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And if you log the unique ID here.

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As you can see where I think I need to type it.

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Well, let me clear it as unique value or unique ID, And we have this symbol and we are not going to

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use this one in this course because it's not commonly used.

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Now let's talk about the non primitive types.

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So I will go ahead and put it here as non primitive data types.

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And one example is the object and object are used to store multiple data about a single entity.

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So it goes like this.

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Let and I want to provide more data about a user.

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And for this one too, we have a section to talk about object functions, strings and others.

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But for the meantime, I just want to show you the different types of data types.

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And for this it goes like key value pair and if I want to save the first name about a user and I'll

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provide as John, it's supposed to be colon but not equal to then comma.

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And if I want to save the last name.

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And I will say, though, as you can see for this one, we can save multiple data in a single value

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or variable.

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And I will say 30 if I go ahead and console log the user here.

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We have all the properties as they stand right now.

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Don't worry about objects If you are new to programming, I just want to show you how it looks like

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and the next type of primitive data type is called array.

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Again, we have a section to talk about array.

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So let me show you an example of code.

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And it goes like this.

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And for this I want to declare a variable called transactions amount and is equal to array like that

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and provide the values here as that so I can save multiple values inside arrays.

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So if I search for transactions amount as you can see, these are the values inside them.

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And lastly, it's about functions.

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Again, don't worry about these ones because these are advanced topics.

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I just want to show you the syntax and example of each of the data types.

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So here I will say let greet user and as arrow function and inside here I can go ahead and console log.

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Good morning.

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Great.

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Save it.

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And inside the console here, if I look for great user and call the function as that I have.

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Good morning.

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At this point, don't worry about the syntax.

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If it looks confusing, we have a specific section to dive in more, but the purpose for this video

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to show you examples of each of the primitive data types.

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All right.

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The next video we will have a look at the best way for naming variables.