Many application settings apply to the active drawing only. These include page layout options, grid and ruler settings, guideline settings, style options, save options, some tool settings, and web publishing options. Saving the current settings as defaults lets you use the settings of the active drawing for all new drawings you create. You can save all current settings as defaults or only specific settings.
If you find that the changed settings are no longer useful, or you no longer can find controls easily; you can restore the default settings by resetting the current workspace.
Resetting the workspace restores the default application, document and tool options. Global options are not reset because they are not stored in the workspace.
Customizations made to the workspace appearance and command bars are lost.