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In this lecture you will learn about the void function here.

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So in some cases you will need to indicate that a function does not have parameters or will not return

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a value.

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So in both cases you can use the keyword void here.

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So let's create an example application about void and then continue our lecture.

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So first void, this function will return a void here.

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So let's for example, let's print a message with this void function with void parameter here, void

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message, void here.

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And then.

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Here.

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Let's print some value.

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For example, no inputs.

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No.

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No.

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Return value.

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Value here.

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And then as you can see, we will not return any value from it because this is a void function and this

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will give us an error.

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So in void functions you can not return a value.

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So this functions in this function has only purpose is to print message on the console here, as you

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can see here.

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So let's write our main function.

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So as you know, main, our main functions does returns something, returns integer 1 or 0, or you

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can return ten, but usually that does not happens here.

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Integer void integer main function.

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And then let's call our print message message function, as you can see here, print message function.

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So now we can run our application, compile our application and run and let's see what our output is.

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So let's run our application.

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And as you can see, no inputs, no return value.

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So the use of void in the parameter list is optional, so you cannot use it as well.

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So an empty pair of parentheses is acceptable and preferable.

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So you don't have to do this all the time.

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It's preferable to just leave it empty.

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You don't need to add void function here, so avoid the keyword here.

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So we will make this empty.

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As you can see here, I did this on purpose to show you why to do this and not so.

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And this is the only way to indicate that the function returns no value other than returning void.

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So note that the void is not really a type because you cannot create a void variable.

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So it is the absence of a type.

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As you will find out in the next lectures, you can create a pointer of the type void, but you will

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not able to use the memory that such pointers point to without casting to a typed pointer.

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So to use the memory, you have to decide the type of the data that that the memory holds.

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So that's it about the void function in this lecture.

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But later on this course you will learn more about the void and void functions here.

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So see you in the next lecture.