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Command-line interface (CLI)

You may be used to using graphical interfaces when using your computer, but initially, interfaces were mostly text-based. This still holds true for a lot of developer tools. There are several reasons as to why but it mostly comes down to that they are easy to create and simple to use. They may feel clunky at first but as soon as you have used a few you will realize that they all follow very similar patterns. Here is short list of reasons for why you should learn to use the terminal.

• Most programming tools are made for the command line, especially with flags allowing for extra flexibility.
• Most unix terminals are very similar, so if you can do something in the terminal on your computer you can probably do it on your friends computer.
• The above point also means you'll be able to get help easier, in courses and in your personal projects.
• It gives you a better understanding of how your computer works, and how it all fits together.
• If you ever need to use a server, or a remote connection you will be restricted to only using a terminal in most cases.
• It's fun! It might seem scary at first but when you get used to it and learn it, it can actually make using your computer a whole lot of fun.

There are two words commonly used when talking about how you interact with text-based interfaces: terminal, and shell. They refer to different parts of using text-based programs, but as it isn't important for this book, we will use terminal to talk about both.

A lot of people naturally get stressed and think that it is easy to write some command that will cause harm to the computer. Please be assured that it is in fact incredibly difficult to destroy anything using the terminal.

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Most systems you will interact with use what is called a Unix terminal. Windows has its own terminals called cmd.exe and PowerShell which are quite different from Unix terminals. cmd.exe is really old and is not used much these days. PowerShell is Microsofts newer replacement, and although it can be used on other platforms than Windows, the most commonly used terminals are still Unix based, and most command line utilities are written for Unix terminals. For those interested, we have a short overview of PowerShell.

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Installation

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To get a Unix terminal on Windows, we need to install WSL (Windows Subsystem for Linux). Open Microsoft Store and search for Ubuntu. Install the first option. You can now search for "Ubuntu" in the start menu and start it that way. This should open a terminal. WSL is a way to run Linux on your Windows PC. You can read more about Linux here.

Important to note is that your WSL install is basically a separate computer running inside of windows. It's a so called Virtual Machine. Feel free to ask dHack or DNS about what this means and we'll gladly talk about it. The reason it matters though, is because programs installed in Windows will not be available in WSL and programs installed in WSL will not be available in Windows.

This is not required, but we also recommend you to install Windows Terminal. It gives a more modern look and feel than the default that comes pre-installed with Windows.

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{{ .macos.linux }} MacOS and Linux already have a Unix terminal and so there is nothing to install.