Notes from Jacob K.:
apropos: search the whatis database
man: format and display the on-line manual pages
man.conf:
whatis: search the whatis database (same as apropos)
info: read Info documents
share/doc/: /usr/share/doc or /usr/local/share/doc/ contains copies of the FreeBSD manual
share/examples/: /usr/share/examples/ or /usr/local/share/examples/ contains copies of default and example configuration files