There are 3 separate but related features that allow you to change the behavior of your keyboard without reflashing. While each of them have similar functionality you access that functionality in different ways depending on how your keyboard is configured.
Bootmagic is a system for configuring your keyboard while it initializes. To trigger a Bootmagic command you hold down the bootmagic key (`KC_SPACE` on most keyboards) and one or more command keys.
Bootmagic Keycodes allow you to access the Bootmagic functionality after your keyboard has initialized. To use Bootmagic Keycodes you assign keycodes starting with `MAGIC_`, much in the same way you define any other key.
Command is a feature that allows you to control different aspects of your keyboard. Command used to be called Magic. Command is typically accessed by holding Left and Right Shift at the same time, although that can be customized. While it shares some functionality with Bootmagic it also allows you to access functionality that Bootmagic does not. For more information see the (Command)[feature_command.md) documentation page.
This table describes the default Hotkeys for Bootmagic and the Keycodes for Magic. These may be overriden at the Keyboard or Keymap level. Some functionality is not available in both methods.
To use the Hotkey hold down `BOOTMAGIC_KEY_SALT` (`KC_SPACE` by default) and the Hotkey while plugging in your keyboard. To use the Keycode assign that keycode to a layer. For example, if you hold down Space+B while plugging in most keyboards, you will enter bootloader mode.
When setting up your keyboard and/or keymap there are a number of `#define`s that control the behavior of Bootmagic. To use these put them in your `config.h`, either at the keyboard or keymap level.