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In the earlier lesson, we briefly looked at declarations versus expressions and for the most part,

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the type of function that we've been writing are the declaration ones.

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And this is also depending on the preference of the developer, you may choose to use the expressions

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or the declarations.

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They're both going to accomplish the same thing, although it's going to look a little bit different

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within the format.

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So some developers will prefer to use expressions and depending on how you want to use them.

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Also, keep in mind, if you are using function declarations, they are hoisted to the top of the code.

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So that means that we don't have to worry about where we place them.

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So in this example, we've got will not work, not hoisted.

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And we see that when we've got the expression function, we're not able to work.

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We already saw that earlier, one of the examples.

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But over here we see where we've got test to that we're invoking.

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And this one will work because this is a declaration.

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So this can sit anywhere in the code.

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So it gives you a little bit more flexibility when you're writing your code to separate it out.

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And you can create a whole list of functions and then you can use them.

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And a lot of times when you've got JavaScript libraries or separate JavaScript files there, declaration

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functions.

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So you don't have to worry about that.

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The where the library is placed, as long as you're linking to the JSC file, then you're able to use

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all of the functions.

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So there are benefits and there are advantages to using either one.

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And again, it's up to personal preference as well as a developer.

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So if you do see that error, then if you are using expression, then that means that you just haven't

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created the expression to find the expression before you're trying to use it in this exercise.

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And this challenge is to create two functions, one as a function declaration and the one the one as

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an expression.

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They can both add a value to a number and they should both work the same way.

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So depending doesn't matter which one we call upon, they should both have an output of ten.

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So obviously, for this example, we're passing in five, it's adding five and it's OK putting it into

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the console.

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So go ahead and try that project out.

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And just so you get more familiar with the different ways to write functions and I'll walk you through

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it.

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So go ahead, pause the video and I'll walk you through it.

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Coming up, the function.

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So this one can be test and it's expecting parameter to be passed.

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And so it's expecting a number and they're both doing the same thing where they're returning a value

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and then just adding five to it.

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And we can console logout test one and console log test two and will pass and five.

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And we now need to define that other function.

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So let's test two.

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And it's taking a number that's being passed in and that's doing the exact same thing where it's taking

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that value that got passed in and adding five to it.

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So try it out.

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And we see within the console we've got two tenths.

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Next lesson we're going to be discussing function scope.

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So let's come up.