McAfee DR SOLOMON S ANTI-VIRUS 8.5 Administrator's Manual page 36

About Dr Solomon's Anti-Virus
Incremental .DAT files are small packages of virus definition files that collect
data from a certain range of .DAT file releases. The latest versions of the
AutoUpdate and AutoUpgrade utilities come with transparent support for the
new updates, downloading and installing only those virus definitions you
don't already have installed on your system. This means a substantial
reduction in download and rollout time, along with similar reductions in
network bandwidth demand.
36 Dr Solomon's Anti-Virus