For some reason, alien entities and super-computers both dislike making anything remotely clear when used by pitiful humans.
Maybe there are endless lines of symbols, shifting colored lights, or lines of normal text spiraling past far too quickly for the eye to see. Whatever the case may be, the characters quickly get the computer or other device to do its job, but God help the audience if they want to know what's going on.
Whatever the case is, the writers need a device to do a job at the character's behest, but don't want to bother showing what's going on in the device. This may be to save the plot, to save money, simple lack of imagination, or the knowledge that Technology Marches On: visible screens from old series look less advanced than your cellphone.
Such interfaces are usually brightly colored and quickly moving, like a visual form of Techno Babble.
Thankfully, our heroes have either already figured out the weird interface, or have a way to bypass it... unless we end up with a Lost Technology Weapon of Mass Destruction, in which case it'll probably take between 30 and 40 minutes to really get a feel for a whole new language and/or thought structure.
This is the opposite of Viewer-Friendly Interface (VFI), in that while a VFI focuses on showing the viewers exactly what is happening in the clearest possible methods, this trope prevents such a thing to the greatest degree possible. Strangely enough, they tend to be found in similar positions on similar shows. In some cases, a VFI and this trope are merely a function of how fast the user types, or an Obfuscated Interface might work as a backup control mechanism for normal devices with more user-friendly controls. If it involves alien technology, chances are you'll have no idea what it's doing until it's done.
- A plot point in the novel Cryptonomicon. Randy intentionally obfuscates his computer's interface with lots of random pop-up windows in order to prevent the baddies who are spying on him from figuring out what he's doing. And what's worse, he wasn't even looking at the screen. The computer told him secret information by blinking morse code through the capslock lights.
- This is parodied in the Star Wars X-Wing novels. Verpines, insectoid aliens, use base six mathematics rather than the base ten used by humans. There have been instances where Verpine technicians inadvertently "fix" X-wing controls to work on base six math, much to the annoyance of the human pilots. Even worse, they occasionally forget that other species don't have microscopic vision and can't see UV light, and so re-jig the instrument displays to be 'more efficient'.
- In Vernor Vinge's proto-Cyberpunk novella "True Names", the Portals used to access The Other Plane are low-bandwidth (to avoid detection), and the interface uses EEG input/output. Just learning to see The Other Plane, let alone manipulate it, requires training and practice.
- Andromeda has a written language that is nothing like English that goes along with all of its displays, signs, even "Happy Anniversary" banners. This makes it even harder to understand the common shots of tactical displays.
- Cylons in Battlestar Galactica (2003) had this. Most of the computer screens in Baseships consisted of pseudo-Chinese glyphs flowing rapidly. Cylons, obviously, seemed to have no problem reading them.
- In the newer episodes of Doctor Who, specifically those with the Tenth Doctor, the TARDIS' screen is seen with post-it notes with Gallifreyan handwriting — consisting of symbols and drawings that only he (or another Time Lord) would understand. The TARDIS also displays information to the Doctor in this language.
- K.I.T.T. from Knight Rider had a bad habit of scrolling thousands of lines of BASIC code through too fast to read whenever analyzing something.
- Land of the Lost's pylons are controlled by a matrix of crystals that have various effects when you arrange them. It's a pity that there's no UI to give you any clue what a given arrangement will do in advance, especially when a bad arrangement can do things like cause the sun to go out.
- Stargate SG-1 shows this one in nearly all alien technology. Crew members repair or disable ships by screwing around with luminous gems. Alien weapons such as hand devices may not even have an interface as we understand it. The stargate itself, at least, is a model of clarity; an astute viewer can even read off the gate codesnote . Alien super weapons tend to overwhelmingly consist of moving rocks. Strangely, all U.S. military weapons and equipment follow Viewer-Friendly Interface criteria, to the point where using the Earth stargate or firing a missile from a converted alien jet involve a nice graphical program with animations.
- Occurs often in Stargate Atlantis as well, predictably. In both shows, this is usually justified by the display being in an alien language (Ancient, Goa'uld, Wraith, Asgard) that the good guys have conveniently learned to read.
- Star Trek features this trope in some scenes. The most notable instance usually consists of the The Spock, such as Data, opening doors or overriding computer controls by switching around randomly placed and colored crystals. Sometimes the normally Viewer-Friendly Interface computer systems will become decidedly obfuscated whenever something needs to be done quickly, or simple plot necessity.
- Half-Life 2: the computers used by the Combine have huge, clunky control interfaces covered in unmarked levers, switches, and buttons, which the increased graphical fidelity of Half-Life: Alyx really lets you appreciate. And thats not getting into the Ominous Multiple Screens they all use.
- The Sims 2's later expansion packs used "Simlish" on signs and stuff.
- Lifted: The UFO's control board has numerous identical switches, none of which are labeled. Even the manual consists of only dots representing switches.
- The Homeworld Gems in Steven Universe use something akin to a keyboard-shaped vat of liquid, which the Gems stick their hands into, causing a bunch of codes to appear in their eyes while they control a spaceship.
- Many Real Life computers (other than Windows) display a couple screens full of text too fast to be actually read when booted. Linux installations typically show much more. In the old days, starting was so slow that the text could be read and technically oriented users often actually understood it. Watching someone use VI or Emacs can also be quite confusing, and using the text console can often lead to a screen full of confusing text.
- Mac OSX does that too, if asked politely. The point is that in case the machine hangs, the last few lines can give some clue about the problem.
- Also, the user base for these computers tends to consist of people who specifically dislike having information hidden from them, and who at least like the idea that they can customize things. Since the text is being generated anyway (for log files), echoing it to the screen is the most direct and modifiable form of display.
- It's also helpful when the computer stops for no apparent reason. By showing the last thing the computer did, and the more knowledgeable will know the next thing it was going to do, one can determine the area the problem occurred in.