System Backup Options 

  Backup Type

 What the Back up Performs         File Properties for Archive Flag

Normal or Full

Backs up ALL files 
MARKS EACH FILE BACKED UP  
 removes the archive flag in file properties.
Differential Backs up SELECTED FILES ONLY 
DOES NOT MARK BACKED UP 
Leaves the archive flag enabled in properties.
Incremental Backs up SELECTED FILES ONLY 
MARKS BACKED UP  
removes the archive flag in properties
Daily Backs up ONLY FILES THAT HAVE CHANGED TODAY DOES NOT MARK AS BACKED UP  
Leaves the archive flag enabled.
Copy Backs up ALL FILES 
DOES NOT MARK AS BACKED UP  
Leaves the archive flag enabled.

                                                                       You will always run a mixture of these types of backups.
  
For example:     Monday you can run a Differential Backup to backup files you have selected and leave the archive flag enabled so your computer system knows they still need to be backed up.  

Tuesday through Thursday you can run a Daily Backup so your computer systems only backs up what files have changed.  This backup is most quickest because only the files that have changed are backed up.

Friday you can run a Normal or Full Backup to cover every file on your computer system.  This backup takes longest since your computer backs up every file.