There are several easy ways to log out from your KDE session:
From the , select the
item.
From the panel, select the
Logout icon, which looks like: 
From the desktop, right-click on the desktop and select
from the menu.
KDE offers you the chance to save your current settings, which will
preserve your panel settings and keep your currently open applications.
If you're working in an application and you haven't saved your work when
you log out, a dialog will inform you that you'll lose your unsaved
material when you log out.
When you see this dialog, you can simply select the
Cancel button, save your work, then log out
again. If you continue without saving your work, you'll lose the data.
