In these complicated times, we welcome simple things into our lives. Faced with Orwellian challenges in a war of words and imagery, we find that having a good arsenal of concepts and definitions is indeed welcome, especially in hardcopy form that maintains information integrity and that can't be redefined or rewritten without consent. So, on a lighter note, an aid for quick lookup of terms from A5/0 to ZRTP, convieniently packaged in book form, is a handy tool.

Jean-Philippe "JP" Aumasson, the author of "Crypto Dictionary" has also authored the book "Serious Cryptography" with the same publisher. So the author is well versed to come up with a Cliff Notes style version for cryptography in only 160 pages. The format of the book feels like an old-school phonebook: the hardcopy I had for review had the black semi-circle tabs imprinted on the edge of the pages, so that you can quickly find references from A to Z by flipping through the pages and "zooming in" on the ones with that starting letter. In case that isn't sufficient, there is an index of terms at the end of the book (aka "criss-cross directory").

Each term is explained in a paragraph or two, from classical cryptography terms such as "Feedback Shift Register" to more recent terms from blockchain such as "Proof of Burn." Interspersed with the itemized explanations, you will find larger text boxes expanding on the topic (for example, innovations of RSA) that is explained on that open double page. Over the course of 160 pages, the author touches on many (most, perhaps not all, as per the author's own admission) important terms and concepts in classical cryptography, and also in blockchain and post-quantum cryptography (for those worried about the looming cryptoapocalypse).

The book feels a bit like reading a more advanced cookbook, where in a particular (and short) recipe the chef will assume you know what a Bavarois is (hint: it's a Bavarian cream) and not delve deeply into how to make one. Similarly here, there are certain assumptions made by the author as to the ability of the reader to understand contextual references. For example, there will be a reference to "Eurocrypt 1990" in the paragraph about a particular concept, but no further detail on what that means (it's the annual European crypto conference sponsored by the International Association for Cryptologic Research (IACR), of course). The author doesn't always take himself too seriously, as there is the occasional poking of fun to be found in here, if only at the international standards organizations such as ISO (just look up "ISO Standard" and you will find a tongue-in-cheek comment).

While there is a companion website at the publisher (http://nostarch.com/crypto-dictionary) with the overview of the book and a list of reviews, there isn't much of a bibliography with a list of academic references for the concepts presented, seminal or otherwise. The reader needs some familiarity with the field (or with online search engines) to look further for deeper explanations, when needed.

This book will sit on my book shelf, to be taken out on random occasions: you never know what you will find while you are looking for some other term in cryptography, a "Denkanstoss" as we would call it in German. To bring it back to the earlier reference, this book is definitely food for thought.

Sven Dietrich reviews technology and security books for IEEE Cipher. He welcomes your thoughts at spock at ieee dot org