A bit short of 150 pages long, it's an opinionated mix of witty definitions, mentions of niche cryptographic constructions and obscure algorithms, historical curiosities, and cryptography nerd jokes, like:
- base64: Not encryption.
- ISO standard: Buy this definition for $180. Please not that a paper format is currently unavailable.
- NESSIE - new European Schemes for Signatures, Integrity, and Encryption: A project that ran from 2000 to 2003 and was headed by seven European institutions. It selected 17 recommended algorithms among 42 submissions. NESSIE's selected algorithms didn't become formal standards, only informal recommendations, which in hindsight drew little interest: does anyone remember ACE Encrypt, SHACAL-2 or SFLASH?
- Proof of work: Cryptography's contribution to environmental problems.
- SUPERCOP: […] In terms of CPU usage, running SUPERCPOP is to cryptography implementers what Bitcoin mining is to cryptocurrency people.
- Time AI™: The Fyre Festival of cryptography
- Trivium: A minimalistic hardware-oriented stream cipher that uses an 80-bit key. For several years, its circular representation was used on the banner of the DEFCON conference website
- Vigenere cipher: A cipher more secure than Caesar's
It's amusing to notice that the background (and strong opinions) of JP. Aumasson perspires in the book: a lot of hash functions, TV encryption, blockchain, … things that would maybe not have been part of the book should it have been written by someone else.
As written in its introduction, Crypto Dictionary is meant to be an entertaining read, so that "any reader can open the book at a random page and discover a yet unknown notion, excavate an obscure concept, or read an anecdote about a familiar term.", and it perfectly fulfils this role, albeit I would argue that some jokes might be a bit too niche/obscure to be understood by "any reader".