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Hello and welcome to this video on javascript functions javascript functions are a block of code designed

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to perform a certain task so the Turbo's group function is executed or called when some team invokes

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it so to invoke it function means you're calling it to perform a task.

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There are many built in functions in javascript.

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You may have come across one before core alert that's responsible for a pop up boxes that comes up on

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the browser.

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You can also create your own functions A Germans group function is defined with the function key word

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followed by the name then followed by per Empathy's you must enclose per hour is function names can

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contain certain letters digits even underscores and their dollars size.

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They also follow the same rules as the variables.

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The parentheses may include parameter may include parameter names which are separated by commas so in

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it parent this is you can add parameter 1 or parameters to be also known as arguments.

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So the code that will be executed by the function is placed inside the curly braces or quarterly brackets

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so they the caudell be executed by the function is placed inside the curly brackets function parameters.

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Are their names listed in the function definition so where you define a function the actual parameters

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are the names.

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But when you actually give the function value being known as argument so function arguments are they

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real values that I receive by the function when the function is invoked or caught inside a function

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the arguments behaves as a local variable.

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That means the variable is only available within the scope of function.

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Function invocation or when you call it function means something happens that will make the function

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to to perform a task.

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For example when you click on a button on the website you are invoking a function.

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Something happens in response to that click is called Click event but is driven by a function.

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Functions also have a return statement so when the javascript function reaches a written statement the

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function will stop executing the code stops so the function was invoked or called from his statement.

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Ben Jealous group will return to execute the code after invoking this statement.

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Functions that often compute Ireton value always return value back to the caller to were invoked the

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function.

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All right this is a sample function I have created that will add two numbers together and return value.

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Functions are very useful in that you can define a function once and then reuse it as many times as

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possible.

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If you think about the alerts function that was the final ones and then you can use it any time you

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want from within the browser.

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All right so this is a function I have written to add two numbers together not to multiply two numbers

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together.

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So this is a keyword function and then giving it a name chord add numbers.

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So it's all in between the parentheses are parameters so the only thing without asserting value inside

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the premises is called parameters to a perimeter parameter number one and then parameter number two.

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So I've also got a variable here called resort and the value only variable is number one times number

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two.

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So I change that to a plus.

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Okay so so the value of this variable result will be a number one plus number to return here.

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The written statement is used to return the result.

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So when you actually pass actual values they're called argument.

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So to call the function created a function here.

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So to call the function.

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So remember my side function now because this is a quote liberators So I'm calling the function outside

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of the function.

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Self CORELY is an alert and I've called it by its name.

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His name is called numbers and I'm giving it to arguments.

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So when you actually pass rule values poured arguments.

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So because he specified here that it takes two parameters 1 and 2.

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So now you are giving me real values which I known R's arguments have given me two arguments and there

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they are.

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So when I executed this alert function this alert function here it will show the results of the number

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of the two values added together.

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Right so this is an alert which is a function on his own built into javascript and then of course my

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own function I've created called Ad numbers so functions are always identified by the parentheses.

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This is my parentheses for my function and I've passed it to arguments.

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So.

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The Argue the values are real record arguments for where you expect something to be passed in the call

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parameters as parameters 1 and parameter to the state.

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I don't know why the vote would be so then known as paratrooper's.

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But when you parse out all values they become arguments.

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So this function here takes two arguments.

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So let me run that and then you see the result.

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They go 16 so it's giving me the result of 16 which is an added number one number two together and the

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result is 16.

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So this is why the alert from action as printed on the screen or displayed on the screen.

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So in this video I gave you a brief introduction to.

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Functions and how they are created and the benefits of having functions.

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I hope the video has been useful.

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If there are parts of the videos or if you don't understand any parts of it please message me.

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I'll be more than happy to help.

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Thank you so much for your time.