The Preferences dialog is the dialog used to set user preferences. It can be found from the main workbench Window menu under Window > Preferences. Preference pages contributed by plug-ins will be found in this dialog.
Most of the functionality of the preferences are defined by their individual pages but the dialog provides two general functions:
Export: Export will write any changes to the default preferences to a user-specified file.
Import: Import will apply the preferences in a user-specified file.
Here is what the preferences dialog looks like: