Your computer keyboard has a processor inside of it, not unlike the one inside your computer. This processor runs software that is responsible for detecting button presses and sending reports about the state of the keyboard when buttons are pressed or released. QMK fills the role of that software, detecting button presses and passing that information on to the host computer. When you build your custom keymap, you are creating the equivalent of an executable program for your keyboard.
QMK tries to put a lot of power into your hands by making easy things easy, and hard things possible. You don't have to know how to program to create powerful keymaps — you only have to follow a few simple syntax rules.
Before you can build keymaps, you need to install some software and set up your build environment. This only has to be done once no matter how many keyboards you plan to compile firmware for.
You'll need a program that can edit and save **plain text** files. If you're on Windows you can make do with Notepad, and on Linux you can use gedit. Both of these are simple but functional text editors. On macOS, be careful with the default TextEdit app: it will not save plain text files unless you explicitly select _Make Plain Text_ from the _Format_ menu.
You can also download and install a dedicated text editor like [Sublime Text](https://www.sublimetext.com/) or [VS Code](https://code.visualstudio.com/). This is probably the best way to go regardless of platform, as these programs are specifically made for editing code.
?> Not sure which text editor to use? Laurence Bradford wrote [a great introduction](https://learntocodewith.me/programming/basics/text-editors/) to the subject.
QMK Toolbox is an optional graphical program for Windows and macOS that allows you to both program and debug your custom keyboard. You will likely find it invaluable for easily flashing your keyboard and viewing debug messages that it prints.
?> If you haven't worked with the Linux/Unix command line before, there are a few basic concepts and commands you should learn. These resources will teach you enough to be able to work with QMK:<br>
Once you have set up your Linux/Unix environment, you are ready to download QMK. We will do this by using Git to "clone" the QMK repository. Open a Terminal or MSYS2 MinGW window and leave it open for the remainder of this guide. Inside that window run these two commands:
?> If you already know [how to use GitHub](getting_started_github.md), we recommend that you create and clone your own fork instead. If you don't know what that means, you can safely ignore this message.
Now that your QMK build environment is set up, you can build a firmware for your keyboard. Start by trying to build the keyboard's default keymap. You should be able to do that with a command in this format: