‫Welcome back.
‫So I hope that you have Node installed
‫on your computer at this point.
‫And so, let's now actually go ahead
‫and use Node for the very first time.
‫And to get started with the section,
‫please go into the course starter files
‫and copy this folder to your working directory, okay?
‫Now, if you didn't download the course files yet,
‫please go to the GitHub repository,
‫that is linked all over the course,
‫and you will find all the files that you need in there.
‫Then after that, go ahead and open up
‫the folder in your code editor.
‫And I'm using VS Code here.
‫And I actually already loaded it up.
‫So here is this Node Farm folder.
‫Now in this video, we will actually
‫not yet start with the project.
‫But instead, we're gonna interact with Node
‫using the command line.
‫And for that, I'm gonna use the built-in terminal
‫that VS Code has, hitting control back take for that.
‫So this command that you see here, actually.
‫Or you can go to View and Terminal.
‫Now if you prefer to use another application
‫for the terminal, that's fine as well
‫but throughout this course,
‫I'm always going to use the terminal
‫that is built in right into VS Code
‫so that we don't have to jump around
‫between different windows so much.
‫Now, to start writing some Node code here in the console,
‫all we have to do is to write node,
‫given that you have Node.js installed on your computer
‫and then, just hit enter.
‫And this will then open up the Node REPL,
‫which stands for read-eval-print loop.
‫So basically here, we can write JavaScript code
‫just like in a normal terminal.
‫For example, we can define variables.
‫And so, here it is.
‫So, we just defined the name variable.
‫And in fact, we can write any JavaScript code
‫that we like in here, okay?
‫So, that's because at the end of the day,
‫Node.js is really just a JavaScript run time,
‫as we just saw before.
‫So what else can we do?
‫Well, any type of expression really, will work.
‫Let's just do some math here, for example.
‫Okay so any JavaScript will work
‫and you see that we actually
‫defined this variable here using const so that is ES6
‫and that is absolutely no problem in Node.js.
‫So it supports ES6 in all the newer versions
‫out of the box without any problem.
‫That's because we're not running
‫this JavaScript in any browser,
‫but it will always run on the server, okay?
‫So, in fact, we just took JavaScript out of the browser
‫and we're running it inside of this Node application.
‫Now if we wanted to exit JS REPL,
‫so again, this read-eval-print loop, that Node gives us,
‫there are different ways of doing that.
‫The first one is to write exit
‫or actually .exit
‫and so this exited this Node process, this REPL
‫and so that started again so that I can
‫show you some more stuff.
‫So again, just type Node, hit enter, and that's it.
‫Oh, and, by the way, if you want to
‫clear your terminal like I just did,
‫all you have to do is to hit command K
‫and that will then clear the command line
‫and probably on Windows, that is control K, okay?
‫Anyway, we use the .exit to exit the REPL
‫but we can also hit control D,
‫and that's not command, it is really control,
‫so control D will do the same.
‫But, let's quickly enter it again
‫'cause there's some more stuff that I want to show you.
‫So if you hit tab right now,
‫maybe you have to tap it twice,
‫sometimes that happens for some reason,
‫but anyway, by hitting tab,
‫you can see all the global variables
‫that are available in Node.
‫So you have all the kind of stuff
‫that we're already used to
‫like the Array constructor
‫or the String constructor
‫or Math
‫or Number over here,
‫but then there's also all kinds of stuff
‫that belongs to Node.
‫For example, your https and fs or crypto
‫and these are Node modules
‫that we're gonna talk more about
‫a bit later in the section.
‫But for now, you see that we have all kinds
‫of global variables that we can access
‫whenever we want in Node.js, okay?
‫Also, another nice trick is the underscore variable.
‫So let me first show you something.
‫So another calculation for example.
‫Three times eight gives 24
‫and now was can use underscore plus six
‫and so this will give us 30
‫and so that means that underscore
‫is basically your previous result.
‫So we had 24, and so underscore here is 24 now
‫and 24 plus six makes 30.
‫So if we now did underscore minus 30,
‫that will give us zero, right?
‫And yeah, it did.
‫Okay, and finally, the tab that you just pressed before,
‫you can also press that, for example,
‫on one of these constructor
‫that we already know like string.
‫So String. and now by adding tab,
‫you can see all the methods or properties
‫that are available to us.
‫Again, sometimes you have to hit it twice
‫but then here we are.
‫So we have, for example, length or hasOwnProperty,
‫and all these kinds of methods here
‫that we know already, right?
‫And now, to exit the REPL,
‫remember all you have to do is hit control D.
‫Okay, then command K to clear the console,
‫and that's it.
‫So that's all I wanted to show you
‫in this very, very first video.
‫So basically that we can write JavaScript now
‫outside of the browser using Node.js like this.