Microsoft Word and Microsoft Excel support saving command bars and keyboard customizations (Word only) in Office documents. Microsoft PowerPoint does not.
Command bars are custom toolbars that can be created in Word and Excel. When data is saved to a Web page, the custom toolbar is not displayed, but the information is saved for reloading later.
Command bar data is saved as proprietary binary data in a file named editdata.mso.
Word also saves keyboard customizations with a Web file using the same data file as command bars.