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So to dive into JavaScript,

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let's get started by understanding Values.

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And what do I mean by that?

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When we write code,

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especially when we write JavaScript code,

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we typically have the intention of manipulating

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what the user sees on the screen.

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Outputting some texts, updating some texts,

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maybe outputting some number, anything like that.

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And therefore, we typically work with Values in our code.

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We might be working with some text,

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maybe some texts the user entered in an input,

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like we did it in this little demo,

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I showed you a couple of minutes ago,

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where we used that user input

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to then count the number of characters.

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And therefore, working with text or strings

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as it's called in programming, is very common.

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And that's a typical value we work with in JavaScript.

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Now, as a side note,

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I will say string from now on when I'm referring to text,

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because that's the official name of text values,

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it's called String because historically we always considered

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text to be a string of characters.

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And therefore, we call text Strings.

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And String Values are one key value type

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we work with all the time in programming.

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But another key value type would, for example,

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be numbers.

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That could be an age of a user or again,

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to come back to that example which I showed you,

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the length of that text.

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So the number of characters off the text the user entered,

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that of course would be a number.

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And numbers are another key value type we work with

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when we write code.

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And there other value types as well,

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which we are going to see throughout

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this course section and this course.

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But text, so strings and numbers are the two,

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I would say most important value types

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you work with all the time.

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And thankfully,

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they are quite straightforward to understand.

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And when we write JavaScript code,

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we often will be dealing with these values.

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We will be transforming text values,

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or we will be deriving number values or making mathematical

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calculations, anything like that.

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Now, when we work with values,

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we typically do that in the context of variables, though.

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And that's another key concept, which you by the way,

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will encounter in basically every programming language

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out there, not just in JavaScript.

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A variable is basically a box, a container.

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You could say variables are labeled data containers.

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And the idea is the following.

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If you have a certain value,

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let's say the text, the string, a user entered,

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or the length of that text.

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So a number.

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Then you might want to store that value in such

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a data container so that you can use it later on

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in your code, in a different operation.

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And you'll see this in action very soon.

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And then this will make more sense.

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But the idea is important that you have values,

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which you want to store in some data container

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so that you can use them later.

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Maybe, also multiple times in different calculations.

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And you do that with the help of such data containers,

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which also have names or labels,

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however you want to call it.

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Which you can choose as a developer to make sure that you

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can later reference the correct data container,

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if you needed.

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It's a little bit like putting an item into a box,

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let's say your tax documents,

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you put them into a box and you put a label on to that box

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that says tax documents.

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And if you then need those documents a year from now,

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or in two years, or at any other point of time,

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then you can just search for that box, thanks to that label,

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it should be easy to find and you can take the items,

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the tax documents, out of that box.

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And it's the same concept applied here in programming.

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But that's the theory.

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Let's see it in action.

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Let's see some concrete code.