This is a standard
It allows you to save your files in an alternative format as explained below. This can be useful if you wish to access the files with a program or device other than DBT.
Note: It is not advisable to simply change the file extension in the File name text box. You should make your selection from the file type list box below it.
The dialog presents you with a drop down list as shown below. (See below for saving braille documents).
The dialog presents the following drop down list for braille documents.
DBT braille (*.dxb) - saves as a current DBT braille file.
DBT Braille, v10.5 and earlier (*.dxb) - saves the document in a pre-10.6 format. If you do this, note that any DBT Codes used which were introduced into DBT from version 10.6 or above will be ignored, and may indeed produce unexpected results if translated or embossed in earlier versions.
Formatted braille, USA encoding (*.brf) - saves the file in the USA braille encoding (potentially different from your currently selected braille encoding).
Formatted braille, local encoding (*.brf) - saves the file in the currently selected braille encoding (as selected in the Global Menu: Internationalization dialogue).
Duxbury coded braille (*.bru) - saves as a text file containing embedded DBT Codes (obsolete).
Refreshable braille (*.lbf) - reformats and saves the document in the linear braille format (including embedded "dollar codes") for a refreshable braille device.