The Man package contains the man, apropos whatis and makewhatis programs.
man formats and displays the on-line manual pages.
apropos searches a set of database files containing short descriptions of system commands for keywords and displays the result on the standard output.
whatis searches a set of database files containing short descriptions of system commands for keywords and displays the result on the standard output. Only complete word matches are displayed.
makewhatis reads all the manual pages contained in given sections of manpath or the preformatted pages contained in the given sections of catpath. For each page, it writes a line in the whatis database; each line consists of the name of the page and a short description, separated by a dash. The description is extracted using the content of the NAME section of the manual page.