Yes, it's amazing. A book this long, and there are still some things that it didn't cover. The footnotes contain additional helpful information.
The purpose of this section is not to teach you about the things listed here, but merely to provide a list. You'll need to go to Programming Perl, the perl (1) or perlfaq (1) manpages, the HTML documents in CPAN's doc directory, or the Usenet newsgroups to get further information.