0.7 How not to get stuck
| Situation | Do this |
|---|---|
| "I don't follow the maths" | Skip it. It's marked optional for a reason. The properties matter, not the proofs. |
| "OpenSSL gave a cryptic error" | Add -text or use openssl errstr <code>. Appendix B has the common ones. |
| "Which algorithm should I use?" | Appendix D is a decision table. Use it. Don't agonise. |
| "This feels overwhelming" | You're meeting 30 years of accumulated attacks at once. Everyone feels this. One chapter a day. |
| "I understand but can't explain it" | You don't understand it yet. Re-read only "How it works", then try again. |
| "Should I memorise algorithm internals?" | No. Memorise what each one gives you and when it fails. |
| "Too many acronyms" | Appendix A is a plain-language glossary. Bookmark it now. |
Honesty markers used in this guide
Simplified: the real story has more detail; here's the direction it goes.
Debated: practitioners genuinely disagree; here are the positions.
Dangerous: a common practice that looks fine and is not.
Facts, standards, and version numbers were checked against primary sources — see Appendix E.