There are so many applications that use the SET file format but the most common application that is associated with it is the Microsoft Backup program for Windows. This application is used to produce Backup file sets and these sets are being stored in files with the SET file extension.
The Microsoft Backup application permits users to generate back up files on the disk using three different types of backup procedures called full backup, differential backup and incremental backup. These procedures function differently but are all stored in files with a SET file extension. Full backup simply backs up all selected files, differential backup backs up the files that have been modified ever since the last backup without marking the files as backed up and incremental backup backs up the files that have been modified ever since the last backup and marks the files as backed up.
Set files also contain at least one of the following switches that guide the Microsoft Backup application in performing its operations: /BW, /LCD, /MDA, and /T[D|I|F]. Each of these switches has their own functionalities that make the backup files more useful.
SET files also contain configuration and settings preferences for different programs that use it. These configurations are loaded when the appropriate application is opened. Some of the programs that reference the SET file format are AutoDesk AutoCAD, Corel Painter, XANA Web browser, Nikon Capture, Diablo II, Alpha Five, and the Sibelius Music Notation application. SET files identify the abovementioned applications’ preferences and so these SET files cannot be opened and modified by other programs except the program that generated it in the first place.