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In this video we're going to introduce javascript methods and we're going to use three built in methods

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which will be useful for the next set of exercises.

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So those methods are alert prompt and console dialog and I'm going to go ahead and make this a little

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bit bigger here.

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One thing you'll notice is that I'm using javascript comments just like in CCS and in HCM all javascript

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has its own way of defining comments which is just notes and things that don't actually run and aren't

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executed.

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So we use double slashes and then whatever I put here won't actually be run.

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So if I did something like five plus 10 which normally would be 15 it just doesn't run it at all.

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So that's comments in javascript.

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I'm also going to show one quick thing here which you'll see me do occasionally which is Cleator my

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console and I type the words clear and follow it with open and close parentheses.

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And I hit enter you know what that will do is clear my console there so clear itself is something called

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a method.

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And we're going to spend a lot of time later in this class talking about method and writing our own

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functions and methods.

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But at their core there's some code that someone else wrote or that we wrote eventually but for now

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there are methods that come with javascript or pieces of code that come a javascript that I can recall

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and I can run.

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So think of it almost as a variable but rather than storing a piece of data like the string hello.

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It stores other javascript code which can be executed over and over.

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So there could be a hundred lines of javascript that when I write clear are being called Clear actually

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happens to be pretty simple but there are methods that will see and that we write that will be pretty

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long.

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So the first method we're going to touch on is called alert and alert is actually a little bit of noxious

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.

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What it does is it pops up a message to the user it alerts the user.

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So the syntax looks like this alert in parentheses.

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And then instead of the parentheses we pass in something that we want to be alerted.

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So I can put a message as a string like hello there.

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And if I hit enter I get this annoying pop up that says the page.

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Google says hello there but I could also give it a number.

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I could have it do a little bit of math in there like 9 teen or 198 times three and four or five and

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it will alert the result.

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So as I mentioned it's a little obnoxious but we're going to use it before we actually build apps that

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display things with each to mount the assess.

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We're going to build apps that just display alerts the next when I want to show is similar to alert

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except it's much less intrusive.

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It's called console dot log.

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And what this will do is print something to the javascript console.

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So if someone doesn't have the console open they'll never see it print.

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So it looks like this con. don't log parentheses and then give it something to print.

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So hello from the console and all it does is just print up that text.

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So just like alert you really only going to use cancel that log early on in this class as a way of printing

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things to ourselves.

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So not printing means to a user you would never expect your user to actually go into the console but

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just for our own purposes.

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And then the last one I want to show is a little different.

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It's called prompt and prompt is very useful for us early on because it lets us get input from a user

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.

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So I'll show you what it looks like prompt parentheses and then inside of the parentheses we give it

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some text to prompt the user with.

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So something like What is your name.

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And if we do that you'll see a pops up or something.

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What is your name.

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And then I can put I can type in my name and hit OK so I'll type something in here and I hit OK.

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And of course it doesn't do anything with that because we're not storing the value.

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So the second part of prompt is that I can store it in a variable so I can save var user name ECOs prompt

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.

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What is your name.

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And this will pop up again.

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I can type something in there.

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I'll do Rusty this time.

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OK.

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Now instead of user name I have Rusty.

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So we're going to use prompts to ask users for input.

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And again we wouldn't use this in a real production web site but for these early exercises it's nice

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to have some variable input coming from a user.

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So the next few videos we're going to build some simple exercises that actually get input from the user