It often takes a teacher, mentor at work, or helpful monk to begin peeling away the confusion.
Indeed. And that all should have happened long before the homework was assigned or interview question was asked.
If you're still wondering what the docs say during homework or interviews, you deserve to fail. Any intercession in that process is just plain ineffective, and does more harm than good in the long run.
-- Randal L. Schwartz, Perl hacker
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.