For questions involved KDE setup, for example

Lane

There's no application called "KDE". KDE (nowadays) refers to the community. If you have a question about KDE Plasma Desktop (or any of the other Plasma workspaces), there's "KDE Workspaces" in the Guided Posting. There's also "System Settings" for questions about settings.

I know it's confusing since many people still say "I use KDE", but we really want to break away from that - it seems to imply that in addition to the KDE workspace, you need to use KDE applications as well. It's all or nothing. In reality you can perfectly mix and match and e.g. use KDE applications in other workspaces (and even other operative systems like Windows and Mac OS X).