A network system includes at least one computer server and at least one
client computer having a printer respectively connected to a network. The
system has a print log generating device that generates a print log having
printer usage contents including software used by the at least one client
computer when a printing request is made in the at least one client
computer. A print log storing device stores the print log, a collecting
device collects the print log from the at least one client computer, and
an aggregating device aggregates usage contents of the printer per a
prescribed category. The print log generating device and the print log
storing device are provided in the at least one client computer, and the
collecting device is provided in the at least one computer server.