Hermes Conrad: Professor, can you wire my head directly into the BattleGrid?This does for computers and technology what Translator Microbes do for living beings. In fiction, all computers, machines, hardware and software are 100 percent compatible and interoperable with each other, and then some. It's as if everything was built according to some universally agreed technical standard. Plug any computerized control unit into any arbitrary machine, and the computer system will automatically have full communications and control over the device, regardless of how superficial the installation is or whether the device even has any electronic components to begin with — if you plugged a computer into a wheelbarrow, your computer would display (in real time) how much potting soil and garden tools it currently holds, and you'd be able to drive it by remote control. A similar phenomenon occurs when two or more computers need to establish a network to communicate with each other. When the intrepid Wagon Train to the Stars makes their first contact with Starfish Aliens from halfway across the universe, nobody ever stops to figure out how those electromagnetic waves emenating from each other's ships are supposed to represent a communications channel (assuming it even is a communications channel at all) ... or how those aliens suddenly managed to hack into the ship's computers (bypassing whatever passwords and encryption) to steal a copy of all their technical schematics and tactical blueprints. Their starships must run on Plug 'N Play Technology! This is obviously not the case in Real Life: Without an agreement for everyone to follow fixed technical standards, computers would not be able to tell their precious 0's and 1's apart from each other in the datastream — compatibility is the exception, not the default. You can't open or shut your closet door by plugging a computer into it, or pick up FM stations on an AM radio. US-made TVs aren't built for the higher voltage levels of European electrical outlets (or the PAL broadcast encoding); you can't play Nintendo GameCube discs on your PS3, you can't run Mac OS executables on the Windows operating system, and the World Wide Web simply would not exist (at least not as we know it) without everyone communicating according to the HTTP technical standard. It's true that at the most basic level, transmissions and instructions are Zeroes and Ones, but there can be no interoperation without a mutual standard for what the binary digits mean, rather like how both English and Spanish use near-identical alphabet but are not, by extension, understood by one another without translation. Not to mention that you also need a standard to know the zeroes from the ones ("breaking the code" for that is easy enough, but plugging two systems with different such standards would be giving Chinese script to someone who can only read English). Plug 'N Play Technology borders on Forgotten Trope territory these days with the widespread adoption of certain technical standards being something that we take for granted, even when it only enables certain kinds of communication between certain kinds of electronic devices. The matter can even be Hand Waved entirely if the fictional devices are, in fact, based on Lost Technology left behind by the ancient Precursors. But don't expect any characters to actually address the matter in fiction (at least beyond declaring that A Wizard Did It), when even the Universal Translator requires time to analyze and decipher the latest new alien language. Please note that this trope has no relation to Plug 'n' Play Friends (which is actually named after this trope's Real Life inspiration), and is not a double entendre for certain adult toys. Related to Possession Implies Mastery, with the computer being the master. Compare Everything Is Online; contrast No Backwards Compatibility In The Future. A biological equivalent is No Biochemical Barriers.
Prof. Farnsworth: I can wire anything directly into anything! I'm The Professor!
Prof. Farnsworth: I can wire anything directly into anything! I'm The Professor!
— Futurama: Bender's Big Score
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- A few Combining Mecha are made of things that weren't originally designed to work together. Examples include Vandread (all components concerned had been extensively modified via Green Phlebotinum), Super Dimension Fortress Macross and a few of the older Brave Series mechs. Worst of all is probably Exkaizer, an alien AI who takes over a car, turns it into a Transforming Mecha, and later gains the ability to combine with other vehicles.
- In Gurren Lagann, the ability to combine mecha is limited only by Rule of Cool, eventually reaching the point of matrioshka like robots that are lightyears in size. In the manga a particularly ridiculous looking combination (the giant Gurren on top and the small Laggan on the bottom) completely fails to work.
- It should be noted that Plug-N-Play Hijacking is explicitly Lagann's special power.
- In the Yu-Gi-Oh!: Bonds Beyond Time, duel disks work with each other even if they're created in completely different eras. (although the technology probably hasn't changed since Kaiba's original design)
- Not only that, but somehow, duel disks that are supernatural, made by aliens from other dimensions, and even organic disks are compatible with the regular ones.
- In Ghost in the Shell: Stand Alone Complex, Everything Is Online and can be easily accessed by plugging leads from a computer into the brain. There never seems to be a problem with interfacing, although there is the risk of having your brain hacked and being forced to act against your will.
- Justified and Lampshaded in Mobile Suit Gundam Unicorn, when Banager takes a Neo-Zeon double beam gatling and plugs it into his Federation-built Unicorn Gundam, it works perfectly without any compatibility errors. The reason being that pretty much all Mobile Suits and associated weaponry is built by Anaheim Electronics, who sell to both sides of the conflict.
- Sword Art Online: near the end of the Fairy Dance story arc, Kirito receives a program from the digital ghost of Akihiko Kayaba called the Seed. Once released across the internet, it became used as a development kit for new VRMMOs, with player data being easily transferable across games running on the same engine. In the Phantom Bullet arc, Kirito takes advantage of this to investigate the murders in Gun Gale Online: while items cannot be transferred between games, Kirito could transfer his experience and stats from Alfheim Online to GGO.
- In A.A. Pessimal's Discworld/The Big Bang Theory crossover The Many Worlds Interpretation, Discworld supercomputer HEX has no difficulties in using and manipulating modern American technology for his own ends, usually with a snarky comment about how primitive or non-existent the artificial intelligence is.
- In Fractured, a Mass Effect/Star Wars/Borderlands crossover and its sequel Origins, this trope is mostly played straight, with a few aversions.
- The salarian Special Tasks Group cannot interface with Trans-Galactic Republic computers to spy on them and are actually caught due to trying and failing.
- Played for Laughs between a mobile shipyard and Trans-Galactic Republic computers—six adapters are required to translate from one machine to the other.
- First averted, then played straight with Element Zero and hyperdrives. The first experiments were disastrous, but later attempts work very well (with other, universe-bending consequences).
- The quintessential example might be in Independence Day, where David Levinson (Jeff Goldblum) uses his Mac laptop to plant a virus on the alien mothership and bring down all the shields. (A deleted scene explains this as human computers being partially back-engineered from alien technology and the scientists having enough knowledge of the captured ship to work out the rest.)
- This one was given a Take That in Stargate SG-1, even though Stargate was itself guilty of this trope at times.
- In the Stephen King movie Maximum Overdrive, the unknown alien force that affects machines serves as the "control box". It's acceptable that a weird alien energy could fire up the electrical systems in machines and make them go haywire, possibly homicidal, so that an electric knife could actually turn itself on. But how does that help the same knife move itself across the table to attack someone? Or how does it allow a truck to adjust its (non-powered) rear-view mirror? Well, it does help when you know that King himself calls the film a "moron movie".
- The My Favorite Martian movie shows Martin replacing his ship's "electron accelerator" with a car's alternator.
- Possibly more of an Expospeak Gag; Alterators/Generators do accelerate electrons.
- The planet Pandora is populated by creatures which have a universal biological cabling system. The planetary Hive Mind can even interface easily with a human brain.
- In Angry Video Game Nerd: The Movie, the Nerd and his friend Cooper are both seen playing the same MMO. While Cooper is using a contemporary computer, the Nerd, who is portrayed as a Disco Dan, uses a Commodore 64 which renders the game's graphics 8-bit style and requires a handheld microphone for voice-chat as opposed to a headset.
- In Dirk Gently's Holistic Detective Agency by Douglas Adams, any computing device placed in a particular place in Professor Chronotis's time machine will interface with the machine and become its control mechanism — even the old-fashioned Professor's preferred device, an abacus. It's explicitly noted that the technology that makes this possible is considerably more complicated than the technology behind the actual time travelling.
- In fact, it's stated that the computer running the time machine is more powerful than every other computer in existence, including itself. And more than 90% of the computer is used for this plug-and-play feature.
- Averted in Soon I Will Be Invincible, where Fatale, only a few years out of date, has a hard time finding a port she can still plug into.
- In Iain M. Banks's Surface Detail, a character defending her home orbital against a massive surprise attack ends up plugging her neural lace into into an ancient, virtually forgotten piece of heavy-duty, last-ditch effort machinery. The author notes casually how two systems written millennia apart perform a standard discovery sequence and quickly agree on an efficient data exchange protocol. (Yes, The Culture is even a software utopia!)
- The Gamma World Choose-Your-Own-Adventure book "American Knights" issues the player with a prototype battlesuit and part-time Robot Buddy named HOBART, who is capable of assimilating technology from the robots you fight on the surface - and justifies it by claiming that as the prototype, HOBART's design is inherited by all the things you cut to pieces and thus he's compatible with just about anything you bolt on to him.
- Knight Rider has done this on occasion.
- It was especially abused in one episode of Team Knight Rider: after transplanting the computer core of one supervehicle into an ordinary sedan (an operation which, it is implied, is hurried and completed within a couple of hours at most), the computer has full control of the vehicle, including the (non-automatic) doors.
- Something very similar happened in Knight Rider 2000, where the original KITT AI gets first installed in Michael's '57 Chevy, and then in the body of the more advanced Knight 4000. Rather subverted, in that KITT's capabilities while in the Chevy are severely limited.
- We can't talk about KITT without mentioning the numerous times he uses his electronic short-circuiting equipment to open mechanical locks.
- The Star Trek: The Original Series episode "The Enterprise Incident": After stealing a Cloaking Device — a big, bulky control unit — from a Romulan ship, miracle worker Scotty manages to wire it up to Enterprise's engines within minutes, whereupon it works perfectly.
- Justified very thinly by the implication that the cloaking device is a single, self-contained unit rather than lots of emitters and other stuff all over the hull; all Scotty had to do was get it wired into the internal electrical grid and fiddle with the field diameter settings. And also by much dialogue from Scotty about how difficult the procedure is, and how the alien device will likely overload systems, blow power grids, etc.
- The Star Trek: The Next Generation episode "Contagion" averts this. When the Iconian virus attempts to operate on Federation, Romulan or Android computer systems, the incompatibilities cause numerous glitches, as well as attempting to rewrite their operating system with it's own. The Enterprise's sister-ship Yamato was destroyed when the virus infected engineering, shutting down the anti-matter containment and causing the ship to blow up.
- Star Trek: Voyager averts this in an early episode "Prime Factors". The crew manages to acquire a long-distance teleporter capable of getting them home and discovers it's completely incompatible with their systems, forcing them to blow it up. They managed to do the same thing with a quantum slipstream drive they encountered later on, again failing because it wasn't compatible and thus had ship-destroying faults, so they dismantled it. They also had a Borg transwarp coil at one point, which plays the trope straight as it worked flawlessly with both the ship and shuttles until it burnt out (though they did have an ex-Borg on hand to help). Averted by Voyager itself, as it's revealed in "The Cloud" that the power system for the holodeck is completely separate and incompatible with the rest of the ship.
- Though the "Prime Factors" instance is literally played straight — the teleporter plugs into a console on Voyager, despite being acquired only moments before, so the crew wouldn't have time to construct an interface.
- Justified in Star Trek: Deep Space Nine where they spend many early episodes on the effects on O'Brien's psyche and stress levels caused by being tasked with getting Federation and Cardassian technologies working (and remain working) together. Several other characters note that nobody else could ever have gotten the station up and running like he did.
- Doctor Who lampshades this in the new series, with the Doctor patching the TARDIS controls with odd items like a bicycle pump.
- As far back as the very first episode of the classic series, the Doctor replaced a "faulty filament" in the TARDIS with something he presumably obtained from 1960s Earth.
- In "Full Circle" the TARDIS happily interfaces with Alzarian technology, which is from a completely different universe.
- Perhaps justified in a Fridge Logic sort of way when you realize that the TARDIS is psychically linked to the Doctor and at least semi-sentient. Presumably any technology he figures out how to use, she can too.
- According to the spin-offs, the TARDIS is built out of mathematics. Presumably all it takes is for her to change a few constants in the equations here and there.
- Partially averted in book The Pirate Loop — at one point, the Doctor plugs the TARDIS into the Starship Brilliant, which apparently gains him full control over the ship's systems. However, the cable he uses doesn't actually fit into the ship's ports, and space-glue is used to hold it into the best port. It still works brilliantly.
- Also mentioned with the newest incarnation of the Cybermen — supposedly they're compatible or able to forge compatibility with nearly everything they come in contact with. The Doctor turns this against them in their first appearance: when Mickey gets the code that will deactivate their emotional inhibitors, all he has to do is text it to the Doctor, who plugs the phone into their central computer.
- It is really remarkable how many devices have a port for the sonic screwdriver. (See "Silence in the Library" for example.)
- This is a core trope of Jake 2.0. The title character is basically a modern-day supergeek — a nanite-powered technopath. Over the course of the show, he learns how to interface with a variety of electronic devices. Most of these make some sort of sense, but in one case Jake remarks "Cars are all computer-controlled nowadays, right?" and then proceeded to stare intensely at a car, remotely start the engine, and drive it through a parking lot as a distraction. *facepalm*
- Of course, there's also the time he nearly got a ticket because he couldn't interface with a parking meter.
- Battlestar Galactica. Athena is a humanoid Cylon based on Kobollian/Old Earth technology that was Lost Forever thousands of years before Colonial civilization rediscovered cybernetics. She resembles a human being to the point that the differences between her and an actual human are almost imperceptible even under a microscope, and she even has a baby with one. And yet, she's somehow able to interface with and control Galactica's computers by attaching a network cable to one, stripping the other end, and jamming it into her forearm.
- In their defense, they probably installed some sort of software package to allow her to interact with the Galactica's computers.
- Also, the Cylons learned to hack the human networks long before Athena defected. She's just running it the other direction for once.
- Stargate SG-1 did this on occasion, but the spin-off series Stargate Atlantis took it to a whole other level, when Rodney would regularly stumble across some long-forgotten piece of technology left behind by the Ancients, and have it running from his laptop (or sometimes his Windows CE-powered tablet) within five minutes.
- Justified in that the SGC has been working closely with Ancient technology for quite a while, so has probably come up with software and hardware to interface human and Ancient devices.
- It's also mentioned that the dialing computer in Stargate Command is only minimally functional: it took them forever to build a computer that controls the Stargate, and even then it ignores half the signals the gate sends it (this is the reason Earth's Stargate malfunctions so often).
- In Stargate Universe, Icarus Base personnel were using a special dialing laptop in place of the planet's DHD. Eli Wallace managed to import and edit Kino video on his laptop. The crew also discovered "recharging" plates which provide power to all of their electric and electronic devices.
- Kamen Rider Dragon Knight: Both Xaviax and the Ventarans use USB.
- Later Kamen Rider Double uses this kind of technology.
- In Dollhouse, Topher develops a device that disables all actives in a fifty foot radius. Bennett Halverson suggests that to disable a specific active at a distance they should just plug it into her computer. That's not what she ends up doing though.
- In the Old World of Darkness setting, the Glass Walker tribe of werewolves devised a magic item called "Vulcan's Interface", which allowed any two electronic items to be linked together in this fashion.
- It is specifically stated in Eclipse Phase that there are no standard software formats. But AI conversion tools are so common that it isn't an issue.
- Warhammer 40,000: Orks can loot anything (steal a weapon or vehicle) and Orkify it (adding guns, spiky bits, guns, flame decals, guns, and maybe a few guns if there's any space left) and make it work, when the laws of physics say otherwise (or explode spectacularly, which to them is just as good). Human techpriests believe that where they entreat and pray to the machine spirits, the Orks just beat them into submission.
- This tends to apply to the Power-Up system in Video Games.
- Most versions of Mega Man have this, as the title character is usually able to use built-in weapons collected from defeated enemies. Handwaved by Mega Man possessing a "Variable Weapons System" which allows him to scan and copy the powers of his defeated foes.
- The Mega Man cartoon takes it even further, where Mega Man is able to not only scan a bomb (not Bomb Man; an actual IED) to gain a complete schematic, he's able to transfer the information to Rush to take to Dr. Light (I guess the system can't work over wireless, only Personal Area Networking).
- In the Mega Man X series, this is further justified by all the other robots being duplicates of X's technology (poor ones at that).
- Legends averts this trope, as Roll has to modify the weapons you pick up in her workshop before you can equip them.
- If you call building fully functioning combat weaponry from a laser pointer modification.
- Averted in one story in Mega Man Battle Network when a virtual idol jokes about being affected by a virus that affects the main characters, but turns out to be unaffected since she is a different type of program. Averted later on with the same character, when she and Mega Man fall in love. Because they are different types of programs, they are unable to even touch each other.
- Justifiable in the first game since Dr. Light actually built the original robot masters, so Mega Man could have been specifically designed to be able to operate their weaponry. Through most of the rest of the series, Dr. Wily could still be using hardware and software similar enough to ex-partner Dr. Light's stuff to still be compatible. Mega Man IV is the first major exception, with the robot masters having been built by Dr. Cossack.
- Strogg computers in Quake IV. Human computers are surprisingly compatible with Strogg computers.
- The cyberjack implant in System Shock.
[The cyberjack implant] is a wonderful piece of kit. You can take anything with a battery in it and plug it directly into your brain. Hoo! Even more magical, whatever you install, it always works and you never ever have an IRQ conflict. So my player is called PNP man (plug'n'play man).
— System Shock Hacker's Guide to Sin
- Justified in Mass Effect, because all advanced technology in the universe comes from Reaper artifacts, made to influence the development of intelligent species.
- In the Metroid series, Samus' Powered Armor is "modular" and can add new gadgets on the fly. It's somewhat justified by both Samus' powersuit and most of the gadgets having at least the same creators (the Chozo), but she can also easily adapt Federation-, Luminoth-, Bryyan- and Space Pirate technology. There are two aversions however; in Metroid Prime 2 the suit can at first not analyze the Energy Transfer Module, and in Metroid: Zero Mission Samus' suit is incompatible with the Plasma Beam-, Space Jump- and Gravity upgrades.
- Subverted in Fallout: New Vegas, where Mr. House had the Platinum Chip specially made so that only certain equipment (equipment he built) could read it.
- But also played straight, in that every single terminal and robot in the Mojave uses Robco code. The terminals even all use the same Robco Unified Operating System. Robco's coding is so ubiquitous that a quest in one of the add-ons is resolved when a sufficiently tech-savvy Courier realizes that the cyborg he's talking to can be understood despite his broken voice module by paying attention to the code fluctuations in his radio chatter.
- Played straight in Fallout 3, it doesn't matter if you're hacking the a home comptuer or a nuclear launch facility, same operating system, interface, same code.
- In Chrono Trigger smart girl Lucca has the skills and knowledge necessary to repair and reprogram a robot from the distant future to be her friend and party member. Good thing the future still uses C.
- Robo's weapons include an arm made from stone from 65 million BC, and one from 12,000 BC. Both flawlessly interface with him, and work better than the one he was built with.
- The Data Uplink in Perfect Dark is compatible with absolutely every computer you come across, including alien starships. There is a loose Hand Wave in that the game's futuristic tech is based on reverse-engineered alien devices, but it's still pretty flimsy.
- Averted in Marathon: sure, you can pick up and shoot the alien guns, but your HUD returns static and an error code in place of an ammo readout. Durandal also provides you with an "alien energy converter" as a stopgap measure, before making your Powered Armor fully compatible with Pfhor recharge stations between games.
- On the other hand, late in Infinity, Durandal (or what's left of him) merges with Thoth, an ancient Jjaro AI whose architecture shouldn't be anything like a human-coded AI's.
- Any obtained weapon, shield, FTL drive, thrusters, or misc. system can be fitten on a specific slot on any ship in Strange Adventures In Infinite Space. Some limitations are added in the sequel/remake Weird Worlds, where fighters can only be fittedn with the most basic shields and short-range weapons. However, there's nothing preventing your Terran ship (considering your people have never encountered aliens before) from finding and fitting a Hyperdrive (which works completely differently from a standard FTL drive) into the same slot in a matter of weeks. You must have some excellent engineers aboard the ship.
- Averted in X Com Enemy Unknown, Dr Vahlen and Chief Engineer Shen have to do a lot of studies and work in order for X-Com to make use of any of the alien technology captured. Played vaguely straight with the Hyperwave device, but it's also demonstrated that the device almost blows out the base's power grid when first activated with the initial surge.
- Toyed with in .hack: following a disastrous computer virus destroying most commercially available operating systems and damaging the infrastructure of the internet, the governments of the world have made ALTIMIT, the only OS unaffected by the virus, the standard OS of all computers made thereafter. With only one OS on the market, all computers became compatible with each other.
- xkcd #644 wants a doctor to install a USB port. The hardware won't work yet, but the patient is hoping the software will come later.
- Justified in Commander Kitty: the iKnow wasn't meant to be used as a Mind-Control Device, but Fortiscue tempted fate by using Zenith's code in them.
- Justified in Homestuck, as the alien technology of Trollian is the same chat client as Pesterchum, just with time-travel capabilities for added frustrations in just trying to have a sane and linear conversation.
- Penny Arcade parodies the use of this trope in Halo.
- On at least one occasion in Code Lyoko, Jérémie has had to borrow one of Odd's portable game systems for a quick memory boost to the Supercomputer. Despite, you know, the fact that the Supercomputer was built anywhere between the mid-1980s and 1994, and even modern computers not having any first-party components that can connect to a video game system or accessory.
- The portable game was connected to a laptop used as interface with the Supercomputer. That still leaves plenty of compatibility questions, though.
- Actually, it could work as virtual memory if the game console had an onboard hard disk. A flash drive would have worked as well.
- A later aversion of the trope occurs when Jérémie has Yumi connect his laptop to a radio antenna by touching loose wires into the laptop's port — there simply isn't enough time to solder a proper connection.
- Lampshaded by Dib of Invader Zim: while attempting to hack Zim's computer, he says, "I only hope the Irkens just happen to use the same operating system as me". Of course they do.
- One particular episode of "South Park" has Cartman buying a Trapper Keeper that can interface to anything, electronic or organic, prompting a Cyborg like the one in The Terminator to return and try to stop it from taking over the world. Rosie O'Donnell becomes involved, and, eventually, Cartman/Trapper Keeper end up an AKIRA-like mountain of flesh.
- On Danny Phantom, Tucker can often stop a technology-based ghost from a handheld PDA. When a future version comes back in time, he comments on how he can still hack him.
Tucker: Wow, I can still hack his system with my PDA. I don't know if that's exciting... or sad.
- Justified (in this particular example) in that the ghost in question had integrated a copy of Tucker's PDA into his suit, and had to obey whatever data was programmed into the PDA. Tucker was able to program the PDA, which in turn "programmed" the ghost. Then again, played straight by the fact that a ghost could even integrate a teenager's PDA into a ghostly mechanical battle suit.
- In the Futurama movie Bender's Big Score, the Professor links Hermes' bottled head up to an entire fleet of spaceships.
- Much of the technology in Megas XLR works this way. While the eponymous robot may be explained as coming from the future and having some of this compatibility built in, Word of God states that the race that built this robot didn't even exist at the time of the story. Also, with some effort, Coop is able to wire a several billion year old intergalactic prison (with English prisoner names into an outdated game console.
- During an episode of The Avengers: Earth's Mightiest Heroes!, Iron Man doesn't know what to do when he confronts a supervillain from a thousand years in the future who has technology that makes his look like sticks and rocks. The situation is eventually solved when he is able to plug his armor into said technology (using apparently compatible jacks on both his armor and the future tech) and turn it off using command overrides that still work because the future tech was based on his. This is similar to saying that a lock maker from the 10th century should be able to open a modern bank vault with his skeleton key because the vault is an evolution of his medieval locks.
- Averted in Transformers Prime: Raf is unable to download a schematic from the Decepticons' computer, because it lacks a port for his flash drive.
- Region 1 (North America) DVD players exist that have the option to output to the European PAL format as well as the North American NTSC format... even though it only has a regular North American power plug.
- "Region 0" DVD players also exist, which can play any region of DVD without any problems. They're particularly common in East Asia, where at least three of these regions exist in close proximity, and people often buy discs from neighboring countries.
- Some DVD players can be "unlocked" into region 0 by entering a special code with the remote.
- Saab market their Gripen fighter aircraft by saying that the aircraft can interface with both NATO and Warsaw Pact weaponry, unlike other fighters of that generation. It's paid some dividends — the Czech Republic and Hungary, both former Warsaw Pact members who are now in NATO, have bought the aircraft.
- Intel Macs can run both OS X and Windows (Not out-of-the-box, some work is required). The reverse (running a Mac OS on non-Mac hardware) is even trickier, requiring third-party software and drivers, copious troubleshooting, and a lot of luck, but it can be done.
- Technically, most if not all Intel machines (Linux, Windows, Mac etc) can run most modern OS's as they are built around the x86 architecture. The only reason you can't easily run Mac on a non-Mac x86_64 computer is because Mac doesn't want to: it checks for a hardware module only present on Mac computers that does nothing but verify that the computer is a Mac.
- Ironically played straight in '70s and '80s, when Soviet Union adopted PDP-11 compatibility as an industry-wide IT standard. It was done exactly for the reason stated above: the interoperability makes life so much easier, and adoption of an already established standard gives you the access to all the software and hardware already developed for it.
- USB-based devices are supposedly this in theory. In practice, you need to install drivers for more complex devices (e.g. cameras, scanners, printers)
- Although many of them are getting better about that. Often the driver is now on the device itself, uses a standard 'profile', or the driver is already on the system (e.g. most legacy hardware.) Pending no problems between the two devices, it'll install itself. Many devices are now Plug, Wait about 30 seconds, N Play. In less common cases, you need to obtain the driver which will just be a simple download as well.
- If it has a CPU, you can run NetBSD on it, period. Linux is a close second.
- If a piece of software has been built to be POSIX-compliant, it'll run on just about every unix-based system out there, or be 90% of the way to working. A simpler piece of software could be made once and then immediately work on $20 embedded boards, Android phones, Macs, and million-dollar supercomputers.
- To an even greater extent, C: if it can compute, there's a C compiler for it. C is the basis for POSIX and Unix and is the lingua franca of the open-source world (and by some estimates accounts for as much as a third of all software ever written). If there isn't a C compiler for your system, don't expect it to see much (any) use.
- QEMU is a CPU virtualizer. If you don't mind some things being really slow, it can theoretically be made to run pretty much any operating system (and by extension, its software) on pretty much any host computer.
- Not QEMU, but same idea: here is an example of stock Ubuntu running on an 8-bit microcontroller. It takes six hours to boot, but it works. The processor is similar to the kind of thing you'd see in a game console's controller.
- The standardized ATX form factor for computer parts insures that anything compliant with the standards will at least fit. Rest easy that you can in fact fit a new top of the line motherboard with a screaming fast CPU, a motherload of RAM and a pair of hyper-fast 3D cards into the case of the PC you initially built in 1999 (and you upgraded the PSU accordingly. A modern PSU will still fit into said case as well).
- There are a lot of standards from the IBM PC that are essentially plug and play. At least in theory. But these standards got incompatible upgrades over time. Only three today are both forwards (supposedly) and backwards compatible: USB, SATA, and PCI-Express.
- The Trope Namer may be the ISA bus PnP standard from the early 1990s. It allowed peripheral cards inserted into one of a PC's ISA slots to automatically determine which IRQ and DMA channels it should use. Previous generations of ISA cards required the person installing them to manually flip dipswitches on the cards to set the IRQ and DMA channel assignment; woe be to the user if you accidentally set two cards to use the same channel. It was widely known as "plug and pray", as in "plug it in, pray it works".
- Interpreted and scripting languages source files, assuming that the interpreter or whatnot and libraries are available to run them, are essentially plug and play programs. You can reasonably expect the same exact source file will run exactly as you expect it from one platform to another.