• When you are Saving, you create an entirely new file containing only what you are now saving. If a file with the same name already exists, that file gets replaced by the one you currently create. A dialog box will warn you about this, and allow you to create a backup file as an alternative. This file will have the same name but it will get the extension "BAK".
Save commands are found in the Studio menu, in the Patch Manager and in the Data Dump Manager.• When you are Updating you are overwriting only parts of the contents of the file. Let's say you are working on some Yamaha SY-77 Voices. On disk you have a file with SY-77 Voices, Multis and Panning data. If you now Update this file, The Voices will be replaced by the ones you have in computer memory, but the Multi and Panning data will remain as they were. Do not confuse Updating with adding: to be able to update a file you must already have some data of the same type in the file, to replace.
For a Device you might be able to handle Names, Data or both.