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All right guys. In this module I'm going to teach you something really really cool and really useful
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as well for any technology, web development or back end development. The command line is going to be your
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friend.
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So let us introduce you to your friend.
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So at this stage you should already have the Hyper Terminal installed and working.
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If you had any issues installing it be sure to check a few lessons back at the troubleshooting instructions.
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It will allow you to access the Bash shell.
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So what is the Bash shell?
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Well to understand the Bash shell we first have to know what a shell is.
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And this graphic is a good way of tackling that.
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So if you think about your operating system as a pistachio nut then the kernel, so the actual pistachio,
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the thing that you're going to eat. I'm really sorry about all the food analogies.
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You can clearly tell I'm pretty much hungry most of the time when I’m recording these videos.
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But let's get back to the topic.
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So if your operating system is a pistachio, then the actual nut is the kernel.
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And in computing the kernel refers to the actual program that interfaces with the hardware.
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So it's the core of your operating system.
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Now the shell of your pistachio or the shell in computing refers to the user interface for you as a
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human to be able to interact with the kernel and in turn with the hardware of your computer.
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And there's two variants to the shell.
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There are graphical user interface shells.
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So for example when you open up finder you're using a graphical user interface to access and find your
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files.
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But there's also a command line interface which is what we're going to be talking about and what we're
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going to be learning about in this module.
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So this is an alternative way of interfacing with the kernel.
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Now it can seem intimidating at first but I want to show you that it's actually super simple.
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And once you understand it you're going to see that it's actually a really really useful tool at your
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disposal.
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So coming back to the shell that we're going to be using which is a Bash shell. And it stands for the
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Bourne Again Shell, and it's named after a Mr. Bourne, but not this Mr. Bourne but this Mr. Bourne. And I
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can attest that they are equally badass. And the Bourne again Shell, or the Bash shell, is a CLI, or a command
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line interpreter, for the UNIX system. And you find Unix based systems or Unix like systems all over the
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place.
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So for example Linux is a Unix like system and a lot of servers will run on Unix and even Mac OS 10
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or the newly named Mac OS runs on a Unix like operating system.
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And this is a completely different family from the Windows side of things, which uses DOS and Windows.
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A lot of things that you can do with the command line can be done using the graphical user interface.
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So why use the command line at all? At the end of the day, what it all boils down to is about greater
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control and in your journey of becoming a better developer you will need to understand and exert more
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power over your tools
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that is the computer hardware.
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But on a more day to day basis you will find that if you are a regular command line user, that it's actually
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easier and faster to do a lot of really common things. For example, inside the terminal, if I wanted to
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make a music folder then it's as simple as mkdir Music,
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and now there it is.
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There's my Music folder. But if I wanted to do inside Finder, for example, I first have to go to Finder,
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I have to navigate to my desktop or whichever directory I want to create it inside and then I have to
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maybe right click, New Folder, and then type something like Music, right?
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And that takes a lot of effort.
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Whereas you know say if I wanted to create Music2, make another folder, it's as simple as hitting the
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up arrow and hitting 2.
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So for me it's a lot about speed and a lot about control.
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The other thing that you'll notice about a lot of these graphical user interfaces is they tried to hide
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a lot of the
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complicated stuff or the unnecessary stuff like configuration files from
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the common user.
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And the idea is that you know unless you know how to deal with it then you probably shouldn't be dealing
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with it.
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But with the command line you have full control and you have a lot of flexibility.
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So for example, right now, let's just delete these two folders that I won't need. On my desktop
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you can only see one folder with no files
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called App Development, right?
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So I’m on my desktop at the moment, inside Finder. But actually, if you use Terminal, you can actually list all
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the files,
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and if I just add this -a flag, you can actually see that I've also got a folder called SecretStuff,
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and you create these hidden folders by simply writing mkdir .Secrets. And now if I list again
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I've now got two secret folders.
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And later on when we're going to teach you Git and version control, we're going to be using the command
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line really heavily to show you the easiest and probably the most popular way, amongst developers at
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least, of using Git and version control.
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So I hope I've sold you on the virtues of the command line.
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So without further ado, let's get started
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learning how to use it,
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what are some of the most common commands, and some tips and tricks as well.