History Main / BlackBox

* Most of the super-advanced technology in the ''WebOriginal/OrionsArm'' universe is at least partly powered by transapientech. This is by definition designed by beings orders of magnitude smarter than ordinary folks. This is something of a subversion in that the inner workings are completely known, and probably published somewhere on the net, but the people using them ''can't'' understand them, since their brains aren't complex enough. It's sort of like trying to teach a small child nuclear physics in depth.

In narrative terms, this is a device that produces [[ClarkesThirdLaw near magical results]] but the comprehension of the device is at best a guess by the characters, meaning [[NoPlansNoPrototypeNoBackup if it breaks a replacement is not easy]]. The original creator is unavailable (either dead, [[ImportedAlienPhlebotinum an alien]] or from [[LostTechnology a long-gone civilization]] or otherwise can't be reached), but said technology is really convenient. Such technology falls into the hands of some organization, usually the military or a commercial business. The organization's analysts went over the thing, and while most of it makes sense, there are these elements, either program or device, [[LowCultureHighTech that they cannot comprehend at all.]] Removing them causes the entire thing to simply not function (or triggers a [[MurderousMalfunctioningMachine more active response]]). The organization may be able to reverse-engineer copies, or lesser versions, but they don't understand how it actually works.

* In ''ComicBook/SuicideSquad'', ComicBook/ShadeTheChangingMan admits that he does not understand any of the principles under which the M-Vest--which grants him his powers--works, as the vest was constructed by Meta's greatest scientist and he was the equivalent of a beat cop. While he understands how to operate the basic functions, he needs the Squad's resources to try and figure out to get it to return him to his home dimension.

* In ''Literature/TheThran'', the whole Thran Empire relies on powerstones as their source of energy, but even the engineers who work on them don't exactly know how they work.
* In ''Literature/SuperMinion'', Tofu relies heavily on a program called human.exe which basically allows him to be as smart as a human. However, he has no idea how the program works, it shuts down if he tries to check its source code, and he doesn't even know where he downloaded it from.
%%* The Strugatsky brothers' ''Literature/RoadsidePicnic'', as well as The Game of the Movie S.T.A.L.K.E.R (but oddly enough, not the movie) have a Danger Zone full of Black Box alien artifacts as the catalyst for the plot.

* From Creator/JohnRingo:
** The ''Literature/LegacyOfTheAldenata'' series features the alien Posleen (or "people of the ships" in their language), who are similar to the Covenant in Halo in that they use technology they understand poorly if at all. One of their commanders stares in confusion at a computer helpfully informing him "Incoming ballistic projectiles. Impact in 10 seconds. Five.... etc" The views of their society in the initial books of the series are vague for the most part but imply that they only really use the systems that kill things or are almost entirely automated. A literal black box used by the humans in the same series appears in the form of the AID which is a black memory plastic box about the size of a pack of cigarettes with an extremely potent AI embedded in it. They act as a UniversalTranslator as well, but are provided by another species and the humans haven't a clue how they really work or how to make them. [[spoiler: This turns out to be a serious problem for a number of reasons]]
** Ringo and Creator/TravisSTaylor's ''Literature/IntoTheLookingGlass'' books has a device about the size of a pack of cards that does "interesting" things with spacetime. It was given to them by the friendly aliens at the end of the first book, who had found it on some other planet and had no idea what it was for. Although they did warn that one should NOT apply a "significant voltage" to it. Hooking up a double-A battery leaves a 10-mile crater. A car battery destroys the (deliberately uninhabited and unimportant) planet. Three-phase current erases the solar system. [[spoiler: They eventually figure out how to turn it into a [[FasterThanLightTravel warp drive]] and use it to power the ASS ''Vorpal Blade''. Turns out hooking it up to a car battery was using it wrong.]]
** The ''Literature/TroyRising'' series: Gravplates are cheap, ubiquiutous, and pivotal to most space travel. Everyone in the galaxy knows how to make them- but the only way to make them requires using gravplates, and nobody knows who the heck made the first one- or ''how''.
* In Robert Jordan's ''Literature/TheWheelOfTime'' there are the ''ter'angreal'' (magical items), the secret of whose making has been [[LostTechnology lost]] for three thousand years. The Aes Sedai keep plenty of ''ter'angreal'' around for use as black boxes without understanding how they work, and many more items where they don't even know what they ''do''.
%%* Parodied in ''The Galaxy Game'' (by Phil Janes) where a scientist trying to master {{FTL}} for a trip to the stars finds three small boxes each printed with the words "Inertialess Device" in his kitchen cupboard one day. We later find out they were put there by bored EnergyBeings who pit civilisations against each other for sport.
* In David Brin's ''Literature/{{Uplift}}'' series, all of the alien species in Galactic civilization are happy to use technology they don't understand and can't repair, so long as it comes with the blessing of the Great Library passed down by their revered ancestors and ''somebody'', somewhere, knows how to repair or replace it. The exception is Humanity, who know darn well that relying on such tech will make them economically dependent on other species. They try to use their own (comparatively very primitive) tech while struggling to learn how alien devices work. Occasionally, Humans even benefit from RockBeatsLaser. But even Earthclan has to rely on Black Box technology for certain things -- i.e. reality shields, psi shields, hyperspace, and the Library itself.
* In Creator/AlastairReynolds' ''[[Literature/RevelationSpaceSeries Revelation Space]]'' novels, everyone uses a certain kind of stardrive, but only the makers know how they work, and fiddling leads to an enormous explosion. The most powerful weapons are barely-understood gifts from SufficientlyAdvancedAliens [[spoiler:or future humans who will send the blueprints back in time]].\\\
Judging by one character's vague discription of the internal conditions in a stardrive in "Weather", the Conjoiners kept the stardrive technology Black Box so that the 'retarded' (everyone else) wouldn't try and weaponise it. [[spoiler: And also because of the whole disembodied-brain thing...]]
* The [=O/BEC=] processors in ''Literature/BlindLake''. Created by accident due to the use of self-rewriting code, not even the scientists who operate them are quite certain how they do what they do. There are only two in existence; all attempts to make a third by replicating the conditions that led to the first two have failed.
* This exact phrase is used to describe the Highway in Creator/WilliamGibson's short story "Literature/{{Hinterlands}}". Astronauts go in and come out, sometimes bringing back pieces of alien civilization with them. The "jump" only happens when the astronaut is alone and they all, invariably, come back either dead or catatonic. Sometimes the jump doesn't happen at all...

* In ''Literature/AtlasShrugged'' [[GrailInTheGarbage the remains of John Galt's motor were found in an abandoned motor factory]]. Dagny Taggart's new purpose in life (for the next few chapters at least) is to find a scientist to reverse engineer the motor and put it to use on her railroad.
** It's a particularly interesting case, as Galt realized that the unbelievable stupidity of Starnes heirs were the symptoms of a cultural decline. He could thus safely walk off and leave [[NoPlansNoPrototypeNoBackup the prototype and the plans]] ''right there in the lab'' without fear that they would be stolen, as no mind capable of understanding how valuable they were, let alone making use of them, would ever work there again. A notable ''subversion'' of LowCultureHighTech.
%%* Colson Whitehead's ''The Intuitionist''. The main MacGuffin in the story is known as the Black Box.
* In Creator/RobertAHeinlein's novel ''Literature/{{Friday}}'' there is the ''Shipstone''; a battery that comes in sizes from a lifetime miniature system for a flashlight, to a large battery that can power a house, to a possibly colossal one that powers space ships. The ''black box''-ness of it comes because the inventor never patented it, since that would require that he publish the schematics. He just started a company and started manufacturing them under lots of secrecy. Attempts at dismantling and reverse engineering a shipstone usually resulted in a big kaboom.
* The Creator/RobertAHeinlein[=/=]Creator/SpiderRobinson novel ''Literature/VariableStar'' has a living black box in the form of Relativists. These are men and women who can coax a ship's engines to accelerate to relativistic speed apparently by [[ContemplateOurNavels Contemplating Their Navels]]. The Relativists think up a number of poetic descriptions of what they do all day to keep the engines going, but in the end they admit that even they aren't really sure how they're doing it.
* In ''Literature/TheHitchhikersGuideToTheGalaxy'':
** The starship Heart of Gold features the infinite improbability drive that enables improbability manipulation up to a point where the ship exists everywhere at once and can drop out anywhere instantly--universe wide teleportation. The hitch is that nobody knows ''how'' the improbability drive really works, some smartass junior scientist just figured out one day that all he needed to know was how improbable it was for that drive to come into existence and ''voila'', [[JustAddWater instant]] Black Box. Then he got lynched by his fellow scientists for being a smartarse.
** The starship ''Bistromath'' works on a similar principle. In restaurants math works differently than anywhere else in the universe. This is why you can never correctly guess what the bill will be, what a proper tip is, how much each person at the table should owe, etc. Nobody knows why this is, or how it works (the attempt to understand it led to a generation of brilliant mathematicians dying of obesity and heart disease), but that doesn't stop them from building a spaceship modeled on a small Italian Bistro to take advantage of this fact and break several laws of physics.
* The Belt of Deltora from Emily Rodda's Literature/DeltoraQuest is technically a Black Box, with the belt part itself the box and the gems the internal mechanisms. It can be assumed that no one knows exactly how it works; indeed, how it works is irrelevant. All anyone knows is that the Belt is "greater than the sum of its parts" and removing one of the pieces (i.e., one of the gems) would stop it functioning.
* In ''Literature/{{Animorphs}}'', the kids are given the power to morph by touching the Blue Box by the alien Elfangor [[spoiler:right before he is eaten alive by Visser Three.]] Later, [[SixthRanger David]] shows up with the same blue box and it is used to give him morphing power even though no one present has any idea how the technology works. [[spoiler: This happens later again when the Auxiliary Animorphs are created, and yet AGAIN when the Yeerks steal the blue box and use the morphing power to create their own soldiers with the morphing ability.]]
* In Ian Irvine's ''[[Literature/TheThreeWorldsCycle Well of Echoes]]'' series, the clankers draw energy from nodes. No one knows why it works, but their are some illegal books that speculate on these topics. This becomes a major problem when [[spoiler: nodes start to fail, because the humans depend upon clankers to fend off the lyrinx that have been killing the human race. ]]

* In Creator/VernorVinge's ''Literature/RainbowsEnd'', pretty much all engineering is done by putting together modular black boxes whose contents are unknown, except to the companies that manufacture them. This is done to protect copyrights and trade secrets. Plus, it's ''supposed'' to make things simpler. At one point, Robert Gu gets frustrated, and tries to open a black box under the hood of a car, using a cutting laser. The result is an explosion.
* In ''Literature/{{You}}'', all of Black Arts's games are based on the WAFFLE engine, but no one at the company really understands how it works. The narration directly refers to it as a "black box" at one point.

%%* In Creator/SergeyLukyanenko's ''Literature/{{Competitors}}'', the alien technology aboard the [[SpaceStation Platform]] is so far beyond human understanding that it took the people sent there years to figure out certain basic things. Unfortunately, most people who end up there lack any technical background, so any engineer who finds his or her way to the Platform is paid handsomely to try to figure out how to even work the systems, much less reverse-engineer them. The engineers also have a fairly high fatality rate due to the fact that they have really no idea what they're doing. Sure, the ships left by the mysterious aliens have fairly basic analog controls (dumbed down for an average human), but it took at least a year to figure out that there are toilets aboard. It took about as long to figure out how to flush one without depressurizing the whole ship. [[spoiler:The aliens are giving bits and pieces of their tech to their human contacts on Earth, allowing their contacts to get filthy rich off the patents]].
* In Lukyanenko's ''Literature/ALordFromPlanetEarth'', many Seeder artifacts are found, replicated, and used, but the principle of their function remains unknown. [[spoiler:This is intentional, as the Seeders are, in fact, [=22nd=]-century humans, using TimeTravel to [[{{Panspermia}} seed the galaxy with humanoid life]] in order to create an instant (from their viewpoint) army in a war. The artifacts were left behind intentionally to help guide their development]].

* In the Russian ''Death Zone'' SharedUniverse, the mechanical artifacts found in the Five Zones usually fit this trope. While people understand that they're a product of MechanicalEvolution from runaway terraforming nanites called skorgs (it turns out that releasing them on Earth instead of Mars was a bad idea), affected by the mysterious Zones, it's almost impossible to reproduce the devices without, basically, copying what the skorgs are doing. This doesn't stop many people, groups, and outside corporations from studying them. Stalkers have also figured out how to use some of the equipment in their daily lives, but they still have no idea how it works.
* In Dave Barnett's ''Gideon Smith'' novels, the British eventually control the mechanical brass dragon, Apep. Apep, despite being made in ancient Egypt during Akneheten's reign, is beyond the ability of a late 19th century {{Steampunk}} Britain. The British would dearly love to copy Apep but can't because of all the {{Magitek}} used in its construction. British scientists have tested Apep and the mechanical doll bound to it, so they know that Apep can fly at 100 miles per hour (and possibly faster than that) and it has an unlimited supply of fireballs that are 1949 Celsius in temperature and these never lose any intensity of heat until they hit a target. However their studies show that the clockwork mechanisms making up Apep, should not have been able to work and they have no idea where Apep's fireballs come from. The only thing they know is that it takes a number of magical artifacts to use Apep.
* The titular Deathly Hallows of ''Literature/HarryPotterAndTheDeathlyHallows'': a wand more powerful (and less "loyal") than any other, an invisibility cloak that never stops working (as invisibility cloaks in that universe are wont to do), and a stone that can summon the shades of the dead from the afterlife. Legend has it that they were created by the Grim Reaper himself and gifted to three brothers. Dumbledore speculates that it's more likely that said brothers were just prodigiously talented magical craftsmen. Whatever the case, no one has been able to replicate their three masterworks.
* Willis Linsay's stepper boxes in Terry Pratchett and Stephen Baxter's ''Literature/TheLongEarth'', which enable people to step from one world to another in an endless chain of parallel universes. They are cheap, easy to build using basic electronic components and powered by a potato. And nobody can figure out how they work. Linsay's daughter is a natural stepper, but since nobody knows how ''that'' works either, it's not clear how it helped him invent the box.
* In the spy thriller ''Running Blind'' by Desmond Bagley, the MacGuffin is a piece of technology couriered by the protagonist who is being chased by Soviet agents. At one point he gets a tech-savvy friend to examine it, who's ends up completely baffled as to what it does. At the end of the novel he discovers that the Soviets were supposed to capture it and waste time and money trying to figure out what it does, which is absolutely nothing.

* [[WeirdScience Wonders]] in ''TabletopGame/GeniusTheTransgression'' work in a similar way to Deadlands: [[MadScientist Geniuses]] can build devices that [[InsistentTerminology delicately bend]] the laws of physics, usually with a [[ClapYourHandsIfYouBelieve crackpot theory]] given legitimacy by [[MagicPoweredPseudoscience the light of Inspiration]]. For many years, various Geniuses have tried to find out the secrets behind Inspiration, with little success.
* Inspired Science from ''[[TabletopGame/TrinityUniverse Trinity Continuum]]'' is developed through means that humans can't replicate. Anyone can use it, but making more requires the inventor to be present (unless it's noetic biotech), and any attempt to explain the science of ''how'' it works to an un-Inspired mind comes across as complete nonsense.

* AI in ''Webcomic/QuestionableContent''. AI don't know what makes them sentient. Even the inventor/"God" of AI, John Ellicott, doesn't understand how artificial sentience evolved, just that "A certain combination of software and hardware led to artificial intelligence, and once we figured that out, we could mass-produce them."
* In a flashback arc of ''Webcomic/{{Gnoph}}'', a scientist criticizes the military for creating a breed of SuperSoldier pretty much by accident and then using them despite not really understanding how or why they work. Sure enough, things soon [[GoneHorriblyWrong Go Horribly Wrong]].
-->'''Dr. Westman:''' Gotta love that military mentality: "Ah don' know why ut works, but they sure do kill!" ''Idiots.''

%%* Some government agents in ''Webcomic/RealLifeComics'' once confiscated an interplanetary ship Tony made. They opened up the reactor and found... ''jam.''

* ''Webcomic/NobodyScores'' has an arc where the main characters end up getting their hands on a literal black box -- things went in, and other things came out. It was when it started producing multiple copies of the severed head of Shia [=LaBoeuf=] (who was still alive) that they started trying to get rid of it...

* An early ''Webcomic/{{Goats}}'' storyline involves such a machine - you put kittens in, and pop tarts come out; nobody knows what happens to the kittens. Later it's revealed that the machine is [[spoiler: a stolen alien spaceship engine, which is powered by the good feelings created when the kitten is placed in a loving home. But it's still a Black Box, because even the aliens don't know where the pop tarts come from.]]
* In ''Webcomic/{{Westward}}'', Escherspace -- a form of FasterThanLightTravel -- appears to be a Black Box. Publicly, the government claims that "only a few scientists" know how it works; in reality, it's strongly hinted that only the mysterious alien Phobos may be capable of understanding it, and he must personally work the controls when the webcomic's eponymous CoolStarship makes an interstellar jump.
* In ''Webcomic/{{Spacetrawler}}'', it's implied that the eponymous spacetrawlers (which the entire galaxy relies on to enable faster-than-light travel and matter synthesis from space debris) are so complicated that only the {{Technopath}} Eebs can understand and construct them. [[spoiler:It's eventually revealed that their construction is less complicated than implied, but the details are so horrific that it's no surprise that the builders insist on keeping them secret.]]

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%% Please do not replace or remove without starting a new thread.

* The development of the Evangelions in ''Anime/NeonGenesisEvangelion'' is very much along the lines of this trope, with Misato even namedropping it in Episode 20. TheReveal is that [[spoiler: they were [[MeatSackRobot constructed using]] [[ImportedAlienPhlebotinum Angel DNA]]]] but due to their EldritchAbomination nature they're unpredictable and dangerous to even use. The S2 engine (recovered from an Angel corpse) is a particularly fitting example. American attempts to reverse engineer the device and implant it in an Eva result in a massive disaster -- the test engine & Eva Unit-04 ''vanishes'', along with the entire research facility and all other objects in a 50-mile radius.
* The [[LostTechnology plants]] in ''Manga/{{Trigun}}'' can do pretty much anything depending on how you power them, but nobody's really sure how they run anymore. (The manga actually calls them "humanity's ultimate black box".)
%%* The flying machines in ''Anime/{{Simoun}}'' have two black boxes: the "Helical motor" (according to the sub) and the "Simoun Gem". Trying to find out how these things work apparently drives you mad for a little while.

%%* ''Franchise/{{Zoids}}''. The Ultimate X zoids are shown to have a "black box" that other zoids do not.

* In the Nausicaa manga, nobody has the technology to build new airship engines any more, so when an airship is downed, there's a scramble to salvage the irreplaceable engines.
* ''Literature/FullMetalPanic'' has a bunch of 'Black Technology', created by the mysterious 'Whispered'. Many are simply extrapolations of existing technologies, which are mass-produced and change the world drastically -- Whispered are explicitly ''not'' [[ReedRichardsIsUseless useless]]. Others, however, are perfect examples of the trope -- Foremost among them is the 'Lambda Driver', a true Black Box which enables users to [[ClapYourHandsIfYouBelieve warp the laws of physics through sheer willpower]].
* TheReveal of ''Manga/OutlawStar''. The eponymous CoolShip and [[spoiler:Melfina]] were created based on the unknown data (the black box) that Gwen Khan could not translate from an advanced ancient civilization which is implied to have created all of the ancient ruins of the galaxy. [[spoiler:Only Melfina can open the door to the Galatic Leyline itself, and grant the people that go there their ultimate desire.]]
** For a while the Caster Gun employed by main character Gene Starwind was a black box of lost knowledge. Caster guns are essentially antique pistols that fire unique shells with a wide variety of effects that can even counteract the magical attacks of Tao Masters. Nobody knows whether they are lost technology or, as later confirmed, magic that has been encapsulated within the shells.

* This is a main plot point in ''WesternAnimation/RobotechTheShadowChronicles''. The Haydonites provide humans with shadow technology which greatly aids them in fighting Invid. But [[spoiler: the technological information supplied by Haydonites is incomplete]], so even though the shadow devices were built by humans themselves, they still have flaws which [[spoiler: Haydonites]] exploit when they attack humans.
* In the American release of ''Anime/{{Voltron}}'' (which combined the separate series ''Anime/GoLion'' and ''Anime/DairuggerXV''), it's established that the Vehicle Voltron was built as an ''imitation'' of the original Lion Voltron built by the late King Alfor of Arus. Since the original Voltron is semi-mystical in nature and the magic was not copyable, the duplicate can only stay [[CombiningMecha unified]] in giant robot form for five minutes at a time.

* In ''Manga/KnightsOfSidonia'' the Kabizashi blades, which are the only weapons that can kill Gauna. No one knows for sure how they work, and no one knows how to make more of them. They were recovered from inside a mysterious BigDumbObject floating in space, and their properties discovered by complete accident. [[spoiler: Production is later established. Understanding? Not so much.]]
%%* The sentinel stations in ''Anime/SoundOfTheSky.'' Felicia points out that they're just checking to see if they still work and there's nothing that can be done if they're broken. Noël even calls them a black box.
* In ''Anime/EurekaSevenAO'', all [=IFOs=] are equipped with a "Third Engine" based on technology found in the Nirvash. They know it can use trapar as fuel, giving the IFO theoretically limitless flight time, and the Nirvash has increased speed and maneuverability while using it, but they have no idea how to turn it on or how it does these things. Elena and Fleur do eventually manage to get theirs working, but it only lasts as long as it needs to for them to rescue Ao, then shuts off almost immediately once he's free. Elena credits The Power of Love, which, given the previous series, is most likely the exact reason it worked. It activates a second time for Fleur in the finale, but nothing comes of that.
* In ''Manga/ToraKissASchoolOdyssey'' we have Academy Island and the Monument. Structures of unknown origins carrying huge amounts of information, some of it on science and technology that are light years ahead of anything on Earth. People can access that information to some extent, but have no idea how the database holding it works or where it comes from.
* In ''Literature/HeavyObject'', the targeting system of Objects requires regular calibrations incorporating the expertiese of three separate engineering disciplines and the intuition of the Elite. Because of the odd interaction between such differing methods and the unique human factor of the Elite, nobody is entirely certain how the system works, only that it does.

* The first three Comicbook/THUNDERAgents were all recipients of black boxes. As their origin shows, their devices were found amid the rubble of the lab of a famous inventor, who had been killed by minions of [[DiscOneFinalBoss the Warlord]]. The Warlord's mooks had looted the place, but missed a few items. Several early stories were about the agents discovering drawbacks to their new powers.
* ComicBook/CaptainAmerica's shield is essentially a Black Box in design; made of an unknown alloy of [[{{Unobtainium}} Vibranium]], other metals and a mysterious bonding agent--which the creator doesn't know about, having fallen asleep during its production--which results in a shield that has properties unlike anything else in existence. Some say that agent was [[RightMakesMight American Rightousness]] (as opposed to [[PatrioticFervor American self-righteousness]]), explaining why it seems to act as almost an EmpathicWeapon to Cap.

* ComicBook/StarLord has his Element Gun, given to him by [[EnigmaticEmpoweringEntity the Master of the Sun]], er... [[{{Retcon}} his father]] when he was just a teenager. Quill's carried it all the way up through to the modern day, but in ''ComicBook/GuardiansOfTheGalaxy2020'', he notes he's modified it, changed its appearance, and even managed to build a spare... and he still has no idea how it actually ''works''.
* ''ComicBook/AtomicRobo'''s heart was constructed by Nikola Tesla using means that not even Robo can even take a guess at, and by the 2010s, the world's leading nuclear physicist couldn't even come close to recreating it even with access to the most advanced lab and unlimited funding. He could make a theoretical copy, but it would only operate half as effectively as the original, would be significantly larger, and would be constructed mostly out of material that ''doesn't exist''. [[spoiler:The eventual replacement is also a black box, which is constructed by delegating the task to one of the world's most advanced AI's, which at that point is in a dead-but-dreaming kind of state, which takes the manufacturing task on board, does ''something'' and spits out a new heart that works slightly better than the original but is just as baffling.]]
* Eega Beeva of the ''[[ComicBook/MickeyMouseComicUniverse Mickey Mouse Comics]]'' is a man from the future with hyper-advanced technology like [[BagOfHolding bottomless pockets]]. In one issue, desperate scientists hoping to secure their funding ask him for one of his gadgets to study. He pulls out a literal black box, claiming it can replicate anything known in his time but, to their disappointment, as far as their instruments can study it's just a solid block of inert molecules, putting them back at square one.

* This exact phrase is used to describe the Highway in Creator/WilliamGibson's short story "Hinterlands". Astronauts go in and come out, sometimes bringing back pieces of alien civilisation with them. The "jump" only happens when the astronaut is alone and they all, invariably, come back either dead or catatonic. Sometimes the jump doesn't happen at all...

** The titular robot of ''VideoGame/MegaManX'' was the last and greatest creation of Dr. Light, who then had X put through 30 years of ethical testing to ensure that he wouldn't misuse his "limitless" power. When Dr. Cain discovered X and studied the robot, he admitted that some of X's systems were "black boxes" he couldn't understand, but did his best to reproduce X's design. The result was the Reploids, a generation of robots more advanced than anything previous, but the fact that they were all imperfect copies of Light's design led to the Maverick uprisings. It wouldn't be until the time of ''VideoGame/MegaManZero'' that a fully successful replication of X's systems would be completed by [[TeenGenius Ciel]]; unfortunately for everyone, Copy X ''didn't'' get the "30 years of ethical testing" and turned into a powerful KnightTemplar that only Zero had a chance of defeating.

* The ''VideoGame/TrailsSeries'' has artifacts, ancient devices that predate the Great Collapse, a disaster of unknown origins 1200 years ago that devastated the world and led to the collapse of society. The Septian Church, the primary religion of the setting, has a policy where they must confiscate an artifact if it is still functioning. They don't apply this to artifacts that have lost their power. The church's justification for this is that because no one knows ''how'' these artifacts work, it's too dangerous to allow an active artifact out in the open.

%%* In ''WesternAnimation/{{ThunderCats|2011}}'', young {{Catfolk}} prince Lion-O is a CollectorOfTheStrange, namely "[[LostTechnology technology]]." He purchases a piece of what he suspects is technology from a FriendInTheBlackMarket, and spends quite a bit of time [[ChekhovsHobby puzzling over it]] and [[SchematizedProp diagramming]] it, but only realizes its function when he sees a Lizard use one to blow up a wall during TheSiege on his kingdom of Thundera. Finally understanding the device's interface as a StickyBomb, he grabs some others to join the fight against the Lizards, saving his father Claudus and brother Tygra by using the bombs to blow up some of the Lizards' {{Walking Tank}}s.

** The fact his documented ideas tended to get stolen (usually by Edison) might have something to do with it.

** On that subject, some (if not most) chemical reactions in general have mechanisms which are only vaguely understood at best.

* The plans for the Saturn V rocket from the Apollo Project are stored in a format that isn't readable by any computer currently in use. Since there are a few leftover rockets that could potentially be fueled up and fired, they have become black boxes. When the new designs for the Orion spacecraft (not the nuclear-bomb one, the newer one) were in the works, the ability to look at the old Saturn design and learn from them was denied the engineers, who had to waste potentially years starting from scratch. Since then, to avoid this trope, a project was initiated to attempt to retrieve the data and transfer it onto a more modern storage medium, but it's so underfunded that it's not currently active.
** Although some of that is true, there are other significant factors involved - for instance, not being allowed to use asbestos anymore even though we know how. It's not ''purely'' a case of "no longer able to read the plans."
** This is an urban myth. The Saturn V plans are stored on microfilm. While readers are not nearly as commonplace as they were at the time of the rocket's conception, they're still readily available.
** Though microfilms do exist, several key parts were destroyed due to Cold War policies on classified materials. The Orion engineers also had access to the engines from one of the original (IXX, I think) F1 engines taken from the rocket currently displayed at the Marshall Space Center in Huntsville, Alabama.
** Adding more to this one - the plans for the Saturn V still exist. However, what has been lost are the many changes that were made at the manufacturing level. That documentation has been lost, for the most part, so we don't know (for example) how the actual F1 engines differ from the plans. This is the real issue in trying to recreate any old piece of technology. It's not just enough to have the dimensions and assembly drawings that show ''what'' you're trying to build, but things like materials specifications and manufacturing practices that tell you ''how'' to build it.

* SR-71 Blackbird recon plane: Due to ongoing modifications to their respective airframes each Blackbird had its own set of blueprints. Thus, each Blackbird was unique, although they looked identical. The original molds or dies used in the manufacturing of the planes were ordered destroyed by then Secretary of Defense [=McNamara=] (Cold War policies again) so it would be nearly imposible to make new Blackbirds or even spare parts (In fact other airframes had to be cannibalized to keep the fleet airworthy), although a lot of planes survive to this day so reverse engineering could be feasible.

* While there is still debate on the subject, nobody knows ''for sure'' why a bicycle stays upright when you ride it. It just does. Numerous theories have been put forth with some of them holding water. See this [[http://www.cracked.com/article_19442_8-simple-questions-you-wont-believe-science-cant-answer.html Cracked article]].
** The same article also lists several other questions that even modern science can't answer: why we sleep, how many planets are in the Solar System, why ice is slippery, how to beat Solitaire, how many animal species exist, what is the length of the US (or any) coastline, how does gravity work. A lot of these questions that we just either never ask or accept a universally-known explanation, which is actually false.

** Sometimes, these machines works, such as the [[https://fr.wikipedia.org/wiki/Affaire_Priore Prioré device]], which seemed to have real effect on cancerous mices but whose secret died along its inventor.
* Any self-taught coder will make these whenever they program... well anything. How bad it is depends on the degree of "self-taughtedness".

** The Japanese have bought a license for an advanced Russian jet. They assemble it exactly by the blueprints, and it turns out to be a steam locomotive. They check the blueprints, gather their best engineers and assemble it again. Still locomotive. They file a complaint to the Russians, so the Russian team arrives, goes into the workshop and shortly produces a perfectly good jet. The Japanese are astonished: "We've tried it again and again and only got a steam train!" "Why, of course", reply the Russians, "did you Read the Fine Print? First you get a steam train. And then you work on it with a rasp."
* For a very common (and far more mundane) example, many, if not most, things that people use day-to-day are effectively black boxes. There is an oft-quoted analogy about how the ability to ''drive'' a car does not equate to an ability to design and ''build'' a car, or even to fix one. For a fun thinking exercise, see if you can actually explain the workings of a microwave oven, or a computer, or a cell phone, or any other number of things you use daily.

** A remarkable example of this effect is describing how, exactly, thermonuclear bombs work: Only the engineers and scientists who have designed them actually ''know.'' Even though the technology is over a half-a-century old and possessed by at least half-a-dozen countries, details of the mechanism have remained strictly classified. The public "Teller-Ulam" design which may (or may ''not'') be the de facto standard for all fusion weapons has been pieced together mainly through inference and assumption, and is quite free of details.

* At the University of Oxford there is an electronic bell that was made in 1840 and is still running today even though the battery has never been replaced, and nobody knows how this is possible because the records of how the battery was made were lost. Even if the amount of power the bell uses is very tiny, an ordinary battery should not be able to power it for that long because batteries lose power over time just from aging, so this is a curiosity. They are waiting for it to run out of power before they take it apart to analyze it, because it might teach us something about how to make longer lasting batteries.

* ''Literature/FullMetalPanic'' has a bunch of 'Black Technology', created by the mysterious 'Whispered'. Many are simply extrapolations of existing technologies, which are mass-produced and change the world drastically -- Whispered are explicitly ''not'' [[ReedRichardsIsUseless useless]]. Others, however, are perfect examples of the trope -- Foremost among them is the 'Lambda Driver', a true Black Box which enables users to [[ClapYourHandsIfYouBelieve warp the laws of physics through sheer determination]].

In engineering terminology, a "black box" is a device with one or more inputs (cake ingredients, an excerpt of text in Mandarin, iron ore), one or more outputs (cake, the same text translated into Frisian, a battle golem), and internal processes that are either:

# irrelevant.

This is surprisingly common in RealLife, particularly in programming, where the programmer is the only one who really understands how what they've built works (and sometimes, not even ''them''[[note]]Even a "simple" (no graphics, purely command-line and input file driven and with the only output being more text files) scientific application that does anything actually useful can easily exceed ten thousand lines of code in a high-level language and is probably the result of the work of multiple people, none of whom knows ''every'' detail of the parts they didn't write. And even if a single dedicated programmer wrote the whole thing personally, it's virtually certain that at least some of it uses infrastructure in the form of library routines or system calls that were not written by the same programmer.[[/note]]). It is something of a RunningGag in tech start-up culture that being the first to design the infrastructure of a new system is ultimate job security, as it would take years for another programmer to understand the coding to the same degree. This is especially evident in high-level languages, where the programmer can for example tell the computer to replace all occurrences of "cake" with "apple" in a text, and doesn't have to worry about how the system does it - they get a changed text back and that's that. This also happens in pharmacology, where it might be discovered that a drug has a positive effect on people with a certain illness but when it's first used doctors and scientists don't understand why.

This is surprisingly common in RealLife, particularly in programming, where the programmer is the only one who really understands how what they've built works (and sometimes, not even ''them''[[note]]Even a "simple" (no graphics, purely command-line and input file driven and with the only output being more text files) scientific application that does anything actually useful can easily exceed ten thousand lines of code in a high-level language and is probably the result of the work of multiple people, none of whom knows ''every'' detail of the parts they didn't write. And even if a single dedicated programmer wrote the whole thing personally, it's virtually certain that at least some of it uses infrastructure in the form of library routines or system calls that were not written by the same programmer.[[/note]]). Especially in high-level languages, where the programmer can for example tell the computer to replace all occurrences of "cake" with "apple" in a text, and doesn't have to worry about how the system does it - they get a changed text back and that's that. This also happens in pharmacology, where it might be discovered that a drug has a positive effect on people with a certain illness but when it's first used doctors and scientists don't understand why.

* ''Film/GodzillaVsKong'': For all of [[EvilInc Apex Cybernetics]]' boastings about human superiority over the Titans, their secret project is actually extremely reliant on seizing outside resources which are eldritch in nature as key materials to make the thing work at all; and Apex intend to use ''both'' resources with only a surface understanding of their capabilities and no true understanding of their inner-workings. [[spoiler:Apex have converted Ghidorah's skull into a WetwareCPU for Mechagodzilla based on their discovery that Ghidorah's remains retain a [[{{Telepathy}} telepathic]] connection to each-other, and]] Apex are planning to use the MineralMacguffin in the HollowEarth as a power source for their superweapon based on their remote satellite discovery that it has high energy readings. [[spoiler:Mixing these two things into a HumongousMecha without an in-depth understanding of either of them ultimately leads to Ghidorah's subconsciousness from the skull taking control of a fully-charged, super-destructive Mechagodzilla for itself]]. "Monkey see monkey do" indeed.

Not to be confused with [[https://en.wikipedia.org/wiki/Black_box_%28transportation%29 "Black box"]] [[https://en.wikipedia.org/wiki/Flight_recorder flight recorders]], [[https://en.wikipedia.org/wiki/Black_box_theater the kind of theatre]], [[https://en.wikipedia.org/wiki/Black_Box_(band) the Italian house music group]] or [[Creator/BlackBox the former video game developer]] who used to make the ''VideoGame/{{Skate}}'' series and various ''VideoGame/NeedForSpeed'' games, or a black-colored CensorBox.

%%* In the ''Franchise/TouhouProject'' ExpandedUniverse, there's a character named Rinnosuke who has the power to immediately identify the function of any device he sees. This does not mean that he knows what it's called or how to use it. He was once horrified to recover a "World Controlling Device" capable of causing great destruction, [[JediTruth little realizing]] that he was dealing with a UsefulNotes/GameBoy.

* For a very common (and far more mundane) example, many, if not most, things that people use day-to-day are effectively black boxes. There is an oft-quoted analogy about how the ability to ''drive'' a car does not equate an ability to design and ''build'' a car, or even to fix one. For a fun thinking exercise, see if you can actually explain the workings of a microwave oven, or a computer, or a cell phone, or any other number of things you use daily.

* For much of the UsefulNotes/ColdWar, nuclear weapons were black boxes, either entirely or to the people working with them. All nukes were designed by multiple people, but sometimes these teams worked loosely with each other in isolation, the effect being that no one person knew how a particular nuclear weapon worked. This method of security eventually fell out of favor as some of the bombs produced by these teams were abject failures; to the extent that at one point in US history, nearly all the warheads carried by US submarines were duds due to their faulty safety systems. In the other case of nuclear black boxes, teams designing [=ICBMs=] and bomb cases were given the bare minimum of information needed to design a delivery system.

* Hex in ''Literature/{{Discworld}}'' (above) was based on one of Sir Creator/TerryPratchett's own computers, a ZX Spectrum he tinkered with and added hardware to until it did what he wanted. Eventually he lost track of it all, and there were components which he couldn't remember or deduce the purpose of, but it you took them out everything stopped working.

* At the University of Oxford there is an electronic bell that was made in 1840 and is still running today even though the battery has never been replaced and nobody knows how this is possible because the records of how the battery was made were lost. Even if the amount of power the bell uses is very tiny, an ordinary battery should not even able to power it for that long because batteries lose power over time just from aging so this is a curiosity. They are waiting for it to run out of power before they take it apart to analyze it because it might teach us something about how to make longer lasting batteries.
* A significant part of TheDarkAges after the fall of the Roman Empire turned a lot of the Empire's technological developments into this. Highly effective concrete, the ability to build aqueducts, their methods of producing weapons and armor, and more were all lost when the Empire collapsed, and it took hundreds of years for society to recover to the point where they could reach and surpass it. In the East this is ''still'' happening with the Byzantine recipe for Greek Fire. When the Empire fell the recipe was lost, and to this day no one knows what was in it in order to make it be able to burn so intensely, even on water.
* A variant of this trope: in ancient times doctors would recommend people suffering from depression and the like drink mineral water from springs. While it worked, they had no idea why. It turns out to be because water from springs tends to contain a lot of lithium, which has an anti-depressant effect and is still used for that purpose.
* In archive science, the "black box" method (devised at the University of Michigan in the 1980s) refers to a schema for making appraisal decisions. The goal was to create a series of questions archivists could ask to evaluate documents, granting a level of transparency to decisions that may not otherwise be clearly motivated -- in other words, to ''avoid'' the black box.

** Secondly, even though in principle the internals of a firm may be examined, most firms are, in practice, very limited in how outsiders are permitted to access their information. While you can, physically, walk into their offices and rifle through their internal files, if you don't have a court order or similar, that's a good way to get [[EnforcedTrope arrested for corporate espionage]]. Likewise, most corporations counsel their employees not to talk to journalists, so you only see the inner workings [[TheStoolPigeon when something seriously untoward is happening]]. So most people treat them as black boxes. Although, like signal processing black boxes, you can learn something about the inner workings from the official accounts, particularly in the case of [[{{Ponzi}} ponzi schemes]], which often grow too fast to be anything else.

* OlderThanRadio: During the early 18th century, Antonio Stradivari hand-crafted several wooden violins that, compared to other violins before or since, produce the highest-quality sound. Many violin manufacturers have, for centuries, attempted to not only replicate the sound of the Stradivarius, but have even labeled violins as "Stradivarius" as a marketing ploy. Unfortunately, when Stradivari died, the technology and skill required to produce a violin of such caliber died with him. Scientists continually do research on the Stradivarius sound and technologies to replicate that sound, and original Stradivarius violins remain to be the most valuable musical instruments in the world.

* The philosophy of ''instrumentalism'' boils down to "the ''only'' important thing about any theory is whether it's usable, i.e. predicts a result of given experiment". Hunting for explanations is but a pointless infinite regression. This means that "light is truly made of particles" and "light is truly made of waves" are fancy statements that delusionally bind real events to imaginary constructs while "wave model correctly and in convenient form predicts diffraction/interference effects" or "particle model correctly and in convenient form predicts absorption/emission effects" states everything that really matters in this issue. From this point of view ''anything'' is a Black Box, the only difference is that we already know how to dismantle some [=blackboxes=] to several smaller [=blackboxes=] and what buttons to push.

** There's also an older theory called classical Newtonian mechanics, which works for medium-size and medium-mass stuff. It was specifically created to avert this trope and describe a Universe governed by simple, understandable laws; it failed at that. However, it works nicely for 90% of the stuff we encounter in our lives, and that's why it, and not GR or quantum is taught at schools.
* The plans for the Saturn V rocket from the Apollo Project are stored in a format that isn't readable by any computer currently in use. Since there are a few leftover rockets, that could potentially be fueled up and fired, they have become black boxes. When the new designs for the Orion spacecraft (not the nuclear-bomb one, the newer one) were in the works, the ability to look at the old Saturn design and learn from them was denied the engineers, who had to waste potentially years starting from scratch. Since then, to avoid this trope, a project was initiated to attempt to retrieve the data and transfer it onto a more modern storage medium, but it's so underfunded that it's not currently active.

** Adding more to this one - the plans for the Saturn V still exist. However, what has been lost are the many changes that were made at the manufacturing level. That documentation has been, for the most part, lost, so we don't know (for example) how the actual F1 engines differs from the plans. This is the real issue in trying to recreate any old piece of technology. It's not just enough to have the dimensions and assembly drawings that show ''what'' you're trying to build, but things like materials specifications and manufacturing practices that tell you ''how'' to build it.

* ''VideoGame/{{Stellaris}}'' generally averts this, and you can scan battle wreckage of even {{Precursor|s}} ships to reverse-engineer their components, but until you have end-game science buildings it's going to take a looong time to complete those research projects. Or you can play this trope straight by taking the "Enigmatic Engineering" Ascension Perk, which makes your technological designs sufficiently esoteric that your rivals can't study them -- a good way to keep the unique technology derived from defeating one of the [[BonusBoss Leviathan]] enemies limited to your forces.

* ''LightNovel/FullMetalPanic!'' has a bunch of 'Black Technology', created by the mysterious 'Whispered'. Many are simply extrapolations of existing technologies, which are mass-produced and change the world drastically - [[ReedRichardsIsUseless Whispered are explicitly NOT useless.]] Others, however, are perfect examples of the trope - Foremost among them is the 'Lambda Driver', a true Black Box which enables users to [[ClapYourHandsIfYouBelieve warp the laws of physics through sheer determination]].

* In ''LightNovel/HeavyObject'', the targeting system of Objects requires regular calibrations incorporating the expertiese of three separate engineering disciplines and the intuition of the Elite. Because of the odd interaction between such differing methods and the unique human factor of the Elite, nobody is entirely certain how the system works, only that it does.

** The starship Heart of Gold features the infinite improbability drive that enables improbability manipulation up to a point where the ship exists everywhere at once and can drop out anywhere instantly--universe wide teleportation. The hitch is that nobody knows ''how'' the improbability drive really works, some smartass junior scientist just figured out one day that all he needed to know was how improbable it was for that drive to come into existance and ''voila'', [[JustAddWater instant]] Black Box. Then he got lynched by his fellow scientists for being a smartarse.

* ''Webcomic/DriveDaveKellet'': The human Empire's Ring Drive. Only members of "la Familia" who rule the Empire are even allowed to see the inner workings, and they don't know how it works, just how to maintain or duplicate it, because their ancestor reverse-engineered it from a crashed alien ship.

* ''VideoGame/XenobladeChronicles2'': [[RobotGirl Poppi]] is an Artificial Blade who is the product of ''three'' generations of brilliant Nopon engineers (Soosoo, Tatazo, and Tora) having created and refined the process, with Tora having actually taken the years of research into the concept plus the experimental [[NoPlansNoPrototypeNoBackup and so-far unreproducible]] ether furnace of his gramypon's design into the process of constructing her. As a result, she has many features that not even her designers fully understand, not helped by Tora being such a recluse [[DoAnythingRobot he added many extra features]], and she has the capacity to upgrade even further.

* ''VideoGame/XenobladeChronicles2'': [[RobotGirl Poppi]] is an Artificial Blade who is the product of ''three'' generations of brilliant Nopon engineers (Soosoo, Tatazo, and Tora) having created and refined the process, with Tora having actually taken the years of research into the concept plus the experimental [[NoPlansNoPrototypeNoBackup and so-far unreproducible]] ether furnace of his grandpapon's design into the process of constructing her. As a result, she has many features that not even her designers fully understand, not helped by Tora being such a recluse [[DoAnythingRobot he added many extra features]], and she has the capacity to upgrade even further.

* The guidance system abroad the Russian communication satellite in ''Film/SpaceCowboys'' is a downplayed example -- it's not an artifact of a lost civilization, it's just so archaic that no-one except the original creator understands it.
-->"It's pre-microprocessor! It's pre-EVERYTHING!"

%%* In ''Film/{{Sneakers}}'' the whole plot revolves around a black box device which is able to decrypt any western encryption (not the Russian encryption-methods, however).

** Secondly, most firms are very limited in how outsiders are permitted to access their information. While you can, physically, walk into their offices and rifle through their internal files, that's a good way to get arrested for corporate espionage. Likewise, most corporations counsel their employees not to talk to journalists, so you only see the inner workings [[TheStoolPigeon when something seriously untoward is happening]]. So most people treat them as black boxes.

** To start with, one of the reasons that command economies are impractical is that much of the information needed to fully plan the economy is locked inside people's heads, where it may be secret, private, or often not even consciously known. Hence, essentially all economic theory revolves around people and firms acting as black boxes, taking in price signals and outputting production and consumption decisions.
** Secondly, most firms are very limited in how outsiders are permitted to access their information. While you can, physically, walk into their offices and rifle through their internal files, that's a good way to get arrested for corporate espionage. So most people treat them as black boxes.