'Notifications' settings control where all text output in DMDirc is displayed. When an event is received, DMDirc attempts to find a setting in the 'notifications' domain with the name of the event. If this setting exists, its value can control where and how the corresponding text is displayed. If the setting doesn't exist, events default to the owning window (so channel events go to the channel window, server events to the server window, and so forth).
Some notification settings are exposed in the preferences dialog under Messages → Notifications. Some of these settings allow you to switch between basic options, and some have some more complex notification targets such as the 'Whois' output, which can be configured to automatically show in the window where you last issued a /whois command for the appropriate nickname. You can alter notification settings using the /set command, for example /set notifications away all will make DMDirc show the “You are now away” message in all windows belonging to a server, instead of just the server window itself. The valid notification targets are described below.