Cybertronian language

It should be little surprise, given a moment's thought, that distinct Cybertronian languages exist. The Transformers did not go about speaking English or any other known Earth language long ages ago on their distant metal world. Though the records of such conversations are frequently translated for us, we should not forget that these conversations originally flowed in odd electronic syllables past strange metallic lips, or were etched by alien hands long eons before the first humans painted muddy shapes upon dark cave stone.

Fiction

Marvel Comics continuity

Jazz made the statement that his real name was unpronounceable in English. Man of Iron

Runamuck and Runabout sprayed Cybertronian graffiti across Earth monuments. They were taken aback to realize that the earthlings couldn't comprehend their alien language wit. Decepticon Graffiti!

The Transformers cartoon

So it's true. The Pyramids were built by aliens.

The first language used by the Transformers was likely the Quintesson language inherited from their former masters. It can be seen upon the walls of the Quintesson dimensional transporter room. It rather resembles Egyptian hieroglyphs. Madman's Paradise

Ancient Autobot, on the other hand, eschewed pictures of birdies.

Ancient Autobot was the language used by the ancient Autobot colonists that fled Cybertron in the distant past. Most modern Transformers (or at least the Decepticons) could not read it. Cosmic Rust

The controls of the Plasma Energy Chamber were labeled in Ancient Cybertronian, which Spike Witwicky did not recognize but Cerebros was able to read. The Rebirth, Part 1

In contrast, the language used by the Autobots when they first awoke in 1984 was easily learned. Spike Witwicky learned to read Modern Autobot after only knowing the Transformers for a single day. (Autobots and humans could also converse freely on their first encounter, though the hows and whys aren't addressed onscreen.) More than Meets the Eye, Part 2

However in the episode "The Golden Lagoon", Beachcomber uses a built-in translation program in an attempt to translate bird song, without much success. Presumably, all Transformers possess this translation program and not just Beachcomber. It's possible that when Teletraan I was first reactivated and went about scanning earth "life forms" that it also scanned and translated earth languages. It could have also downloaded it into each Transformer as it repaired them, explaining why both the Autobots and Decepticons could speak English right off the bat.

Beast Era

See Cybertronix, Vok symbols

2001 Robots in Disguise cartoon

While many of the Autobots' readouts used a code utilizing the Latin alphabet, their heads-up displays also included text in Cybertronian script.

Cybertron cartoon

Writing was displayed on a viewscreen of the starship Atlantis. Ship

IDW Generation 1 continuity

See Ancient Cybertronian, Chirolinguistics

Cybertronian language changed over time, from Old Cybertronian to Neocybex in modern times.

When it came to alien languages, Cybertronians could speak and understand them moments after landing on the planet. Cliffjumper couldn't explain how it worked; it just did. Spotlight: Cliffjumper

Alien writing was displayed on a computer screen that Wheeljack was working on. ...For All Mankind

Animated continuity family

Animated cartoon

There was writing outside of Jazz's quarters on the Elite Guard flagship. Five Servos of Doom

Later, Bulkhead left yellow PostIt-style notes on his space bridge controls. Ratchet had a hard time deciphering them, as Bulkhead's servos were not designed for "penbotship". This Is Why I Hate Machines

The AllSpark Almanacs

Archaic languages on Cybertron included Old Malignus and Destron. The AllSpark Almanac II

The Arrival

As Ultra Magnus and the Elite Guard reviewed what they knew about the first battle between Optimus and Megatron, an image of the Nemesis appeared on a screen with labels in a written language. Dispatches

Live-action film series

See Cyberglyphics

Ghosts of Yesterday

As they fled from the Ark, the crew members of the vessel Ghost 1 were able to pick up the transmissions from the Autobots. They thought that one might be able to make out words from the spoken language of the Autobots if they had a degree in theoretical physics...and were tripping on bad acid. Ghosts of Yesterday

Transformers film

The Decepticons communicated with each other in a spoken language, which to human ears sounded like a collection of vowel-intensive electronic noises and rumbles. They had also learned enough English to communicate with the humans when necessary. Cyberglyphics convinced Sector Seven that there was some relationship between Megatron and the AllSpark. Transformers

The AllSpark Wars

Agoraptor and Agoracer each communicated in a kind of code, based on Cybertronian lettering. AllSpark Wars

Dark of the Moon video game

Mirage encountered a Mayan temple that was built on top of an ancient Decepticon base. After entering the structure, he noted that the walls were covered in ancient Decepticon Hieroglyphs.

Shattered Glass

The Around Cybertron news program featured both advertisements and a news scroll at the bottom of the screen written in Autobot text. Hasbro Transformers Collectors Club #28

An Autobot stellar spanner was marked CWP274 in Autobot characters.

Elsewhere, a box in the Decepticon Base was marked 'fragile' in Decepticon characters. Blitzwing Bop

Aligned continuity family

War for Cybertron video game

On many computers, consoles, and screens on Cybertron, Cybertronian scripts could be seen. When a directive was shown to a Transformer, symbols flashed on their heads up display. War for Cybertron

Prime cartoon

When Bulkhead's mind started to be assimilated by information ejected from a data cylinder, his mind went to science and formulas. He began to eccentrically paint Cybertronian symbols on chalkboards and walls, using a broom like a paintbrush. T.M.I.

2015 Robots in Disguise cartoon

Toys

Universe (2008)

- Series: Classic Series

The packaging art for many of the "Classic Series" toys in the 2008 Universe toyline features movie-like "tribal markings" on the characters, going along with the more movie-like renditions of the characters.

More directly, the Legends-class Cosmos toy has his name written on his vehicle mode in Cybertronian lettering.

Timelines

Banzai-Tron features his original Tech Spec motto, "To the victor go the profits," in Autobot text along the side of his vehicle mode.

Kre-O

The Orion Pax Kreon that comes with the Transformers: Kre-O Character Encyclopedia has a clear 1x2 plate accessory with "KREO" in Autobot text.

Notes

"...For All Mankind" uses the Star Wars Aurebesh script to represent Cybertronian writing.
In the late 90s, Jim Sorenson created a full "Ancient Autobot" font based loosely on the symbol writing seen in "Cosmic Rust," and a "Decepticon Graffiti" font based on Runamuck and Runabout's graffiti seen in the Marvel comic. Both these fonts have gone on to see official use in Transformers media; Agoracer and Agoraptor used the fonts associated with their respective factions for The AllSpark Wars game; the Decepticon font was used as part of the Revenge of the Fallen video game; and the Autobot font was used to hide hidden messages in Sorenson's AllSpark Almanac series of books, as well as on Banzai-Tron's Timelines toy, on Burger King's Transform Your Way promotion, as a part of the Around Cybertron news broadcast, on the cover to "All Hail Megatron" volume 3, in Rescue Bots and in Age of Extinction.
For the War for Cybertron video game, High Moon Studios created their own Cybertronic alphabet also based on the symbols from "Cosmic Rust". It appears in various places through the game series, and was used on the Torchbearer toys.
Might we just kindly point out that this is not how foreign languages actually work in real life.