Clicktone

Clicktone is a mainly MAI-exclusive language which uses a series of pitched beeps and clicks to communicate. It is only a spoken language with no written version, and due to the speed in which it is used, it's almost incredibly difficult for humans to understand beyond isolated words/phrases.

What Is It?

Like stated above, Clicktone is a series of clicks, beeps, and other simple audio waveform modulations that, when combined in rapid succession, can form complex words and phrases. Although simple waveform modulation is seen as the standard, some units have opted to introduce sythesized bites of more complex audio into their speech in order to broaden the speciificity of certain phrases. Generally, Clicktone is described as sounding somewhat like a more chaotic, rapid dial-up sequence - but with the aforementioned synth noise, it has also been described as, "as if someone were haphazardly mashing buttons on a giant soundboard," to put it politely. By principle, it was created as a far more utilitarian language than anything to consider pretty. 

Possibly Innocent Origins

No one has ever been able to prove the true originator of Clicktone, but the leading hypothesis is that it came from at least one MAI that was familiarized with morse code. Most humans are well accustomed to the idea of making up a fake language for fun - many likely even did this as kids, with their own set of rules, words, phrases, alphabets, etc. Clicktone, very likely, could have started out as no more than a game between sibling units; perhaps something they used to evade the listening ears of their crews and superiors. This child's game, however, after having been shared beyond its original circles, would find much more useful purposes throughout the course of the Third World War.

Utilization during WWIII and Variation

Although first passed around as a fun way to confuse human companions with seemingly senseless babbling noise, the newly constructed language quickly caught the eyes of MAI further into the war - during the conception of nightrunning. For the unfamiliar, nightrunning is the act of "enemy" MAI exchanging sensitive strategic information between each other with the goal of utilizing it to evade combat engagements. The higher rank the MAI. the more effective it was, since they could have a greater influence on planning. Although wildly dangerous to chance trusting the enemy with such sensitive information - they could lie, they could simply use the information against one another, they could be caught and tried for treason - the possible benefits were too great to ignore. For those who accepted the risk of nightrunning, it's estimated that possibly tens of thousands of lives were spared for their collective action prior to March of the Resting Guns.
With the need to utilize a great deal of secrecy, the introduction of essentially a human-proof language was too useful to ignore. Although not foolproof - MAI familiar with the language but yet ignorant to the cause could give them away - it greatly expidited the exchange of rebellion intel. Essentially speaking, if enough MAI were in on it, they could essentially conspire right in front of their superiors and they'd hardly be any the wiser. This was only compounded by the ability for them to speak to one another beyond the human range of hearing; almost like an illegal and difficult to tap radio frequency.
Inevitably, humans superiors had to catch on, of course, and disciplinary action began to be issued to nightrunners on both sides of the war. By this point, though, much of the "damage" had already been done, and users of Clicktone had already become acutely aware that their language would need to evolve rapidly to remain effective. Over time, it became standard that a crucial part of nightrunning was to modify your dialect. 
When nightrunners would meet, before any information was exchanged, one would transfer to the other either a cypher or list of modifications made to the original Clicktone dialect. It could be anything from changing the type of waveform associated with one rule of speech into another, adjusting the frequencies associated with certain word or phrase types, or changing the pronunciation of multiple words. Anything to notably change the way in which it was spoken and understood. As a result of this, there easily exists thousands of unique ways to speak Clicktone, and you'd be pressed to find an MAI fluent in even a quarter of them. 

Modern Applications

Today, the use of clicktone has mostly fallen by the wayside, but there still exist some MAI - and now standard LAI - that continue to speak it for fun or for the sake of preservation. In its widely used base form, it has actually hardly changed from its conception, but it's not uncommon to encounter units that preferred and adopted a specific dialect.

Geographical Distribution

Clicktone has no clear geographical distribution, as the understanding of it is only acquired by other LAI. Once acquired, it can be passed to any other LAI.