ARCHIVE

Every file has a flag associated with it (called the archive attribute) that 
is set by DOS when the file is modified or changed. This flag is used by the 
BACKUP and XCOPY commands to decide which files need to be backed up. BACKUP 
or XCOPY clears the flag after backing up the file. The ATTRIB command can 
also be used to clear or set this flag, or even show the flag on a directory 
listing (DIR doesn't show it).

The other attributes (characteristics, properties) that DOS keeps track of for
each file are described in the DIRECTORY definition.
