Every possible user input in Doom Builder is turned in an "action". You can change or assign new controls to these actions in the Preferences Dialog on the Controls tab. Some of these actions are available in all editing modes, which other actions are only available in one or more editing modes. Therefore, you can often re-use the same keys for multiple actions when they are in different editing modes. All the available actions that come with Doom Builder are explained in this part of the Reference Manual.