man(1) exiftool
an interface to the on-line reference manuals
man  is  the  system's  manual  pager. Each page argument given to man is normally the name of a program,
utility or function.  The manual page  associated  with  each  of  these  arguments  is  then  found  and
displayed.  A  section,  if  provided,  will  direct man to look only in that section of the manual.  The
default action is to search in all of the available sections, following a pre-defined order and  to  show
only the first page found, even if page exists in several sections.
source manpages: man