[Note that So, you've just been turned into a zombie has been retroactively added to the Zombie Survival Guide]
To say that the decovery that the groans, moans, and other assorted sounds zombies made constituted a langues is the greatest revelation of the entire conflict is true, but misleading. It is misleading because it understates the importance of the revelation.
One expects a revelation to change things, but not to change everything, and this one did.
It did not because it gave us insight into what was going on inside of zombies minds, but because it made us realize that they had things going on inside of their minds. All of our previous dealing with them assumed that they were mindless, a fact that, it would seem, they were able to exploit to their advantage.
It answered the question that we had since the beginning, which was how the hell did the outbreak become global. How could unthinking monsters driven by the most basic of needs ever manage to break our quarantines, evade our detection, and spread to every inhabited land? The answer: they didn't. Thinking monsters did. Ones that understood that detection likely meant death and were able to stow away on this or that ship or plane and make it to virgin shores and, once there, spread the infection.
It also revealed that we're at a distinct disadvantage when it comes to understanding. They understand us and our various languages, we do not understand them and theirs. As Leopold Bloom said of his cat, "They call them stupid. They understand what we say better than we understand them. She understands all she wants to." And the truly frightening thing is that a zombie is more likely to recognize that reference than a human.
But before I get to that I should address some things.
The first is that we do not understand the Zombie Language. We have not cracked it. So, you might be wondering, how could I have translated this text? The answer is simple, it was never in the Zombie Language. Only one composition uttered by zombies has been deciphered (this one, if it wasn't obvious) and the reason it has been deciphered is because it isn't in their language. It's in English (and French, and Spanish, and Russian, and presumably every other language. Fragments in Kurdish have been recorded.)
This composition is uttered to newly created zombies and while it is uttered in the zombie mode of speech, based on what we have able to determine it is always spoken the language of the humans newly turned into zombies, or as close as the uttering zombie knows. (Never in the Zombie Language itself.)
This may indicate that there is some transition period during which a zombified individual still thinks in their native tongue, or it might be to ease he transition from human to zombie, or perhaps there is some other entirely unrelated reason for this.
The result is  a bit like we encountered a language we didn't understand in an alphabet we didn't understand, and then we discovered that one work in that alphabet was just English in another alphabet, were hopeful that the rest were too, and discovered that that wasn't the case.
We now understand that zombies talk, and how they talk, but we still haven't discovered what they are saying, except for the one case where the speak it in a different language.
This case, this composition, has been dubbed "The Zombie Survival Guide," and it is exactly what it sounds like, a composition designed to help newly created zombies survive. As it is the only composition we have been able to translate it offers our only glimpse into what zombies think, how they think, and what they think of us.
One thing that is remarkable about it is the lack of variation evidenced in it.
It does vary some by region sections have been added or subtracted as time went on. Pop culture references will be adjusted to fit the audience as evidenced best by recordings from the Green Springs Rest home as compared to those recorded at the fall of certain high schools. But overall the text does not change. At all. Except where necessary for meaning to be conveyed to the audience because the audience wouldn't understand a given reference or idiom, the text remains constant in all recordings.
It never changes.
This implies perfect memory on the part of zombies, they transmit it as it was transmitted to them unless a change is necessary (and as mentioned before, it has been translated into various languages.)
Consider the opening sentence: So you've just been turned into a zombie. In every recording where zombified English is used it translates that way. Never "Well you've just been turned into a zombie," never, "So you have just been turned into a zombie," never, "So you've just become a zombie."
This is what I mean when I say that a zombie is probably more likely to recognize the Leopold Bloom reference above than a human reader. If they every encounter Ulysses in their human life, on becoming a zombie it seems like they wouldn't forget as a zombie, and they could easily go on to transmit the text to every other zombie they met.
The disturbing thing about this is what other things might have been transmitted. Many police and military personnel have been turned, it is not unreasonable to think that zombies now know all of our tactics.
I'd like to close by saying this:
I know that I have been blessed. I've been blessed to survive this long. I've been blessed to find myself at what has become a communications hub. I've been blessed to have the equipment to analyze zombie vocalizations, and to turn what look like messy sign waves into readable text. I've been blessed to be able to make contact with others working on the same topic. Most of all I've been blessed to have the leisure time to do all of this. Not something most people can lay claim to in this day and age.
I have found myself in a position of extraordinary privilege, and when I will continue to use that to decipher the Zombie Language itself, I don't know when or if that will yield positive results.
This book is my attempt to pay the world back, in some small way, for the privilege I have been given now rather than later. I have searched for the best recordings, I have tried to choose the idioms and references most likely to be understood by those likely to get their hands on a copy of all of this.
Most of all I have tried to faithfully transmit to you the only translated Zombie composition so that you might learn what the enemy is thinking, and hopefully translate that knowledge into an increased chance of survival.
 This is a massive oversimplification. I want this work to be accessible as possible because I want as many as possible to know what little we do know about the zombie mindset so that, by knowing our enemy, we may better oppose our enemy.
In truth it's much more complicated. First off, zombies don't use letters. They use micro variations in pitch and volume and the magnitude and length of those variations both are taken into account. While an alphabet can be seen as a linear method of information communication (from the first letter to the last) this allows for four axes of information. The length of the variation in pitch, the magnitude of the variation in pitch, the length of the variation in volume, the magnitude of the variation in volume. And there are more than 26 options in each direction.
These variations are very small and very short, which was one of our most definitive proofs that the zombie sense of hearing far exceeds our own, and the result is that massive amounts of information can be communicated very quickly.
At the beginning of every vocalization is a sort of key which lets other zombies know the vocal range that will be employed, as well as what language will be used. When the Zombie Language is used this "key" is more complex and we believe that the result is that ever groan or moan has it's own encryption, with an encryption key attached to the beginning. Until we've learned how to read the encryption keys, comparisons of zombie vocalizations are not likely to be nearly as useful as they might be. We can only compare those that have the same key, and try to extract information from that, rather than using the whole of recorded zombie vocalizations as our starting data.
In the zombie version of English words are spelled out, with some of the more common words having their own micro-variation assigned to them. This communication in "spoken writing" eliminates any possibility for confusion based on accents. Examinations of the last transmission from the British Isles, the so called "Fall of London recording", indicates that zombies do take regional variations in spelling into account.