Warnings are usually in the header or metadata part of fanworks that warn readers or viewers of potentially disturbing content, including but not limited to graphic sex, violence, chan, rape or non-con, BDSM or other kinks, foul language, character death, triggering depictions of mental illness, spoilers, slash, het, homophobia, or a host of other possibly offensive elements and squicks and triggers. Many fans also expect a warning for an unhappy ending, such as their OTP not getting together or breaking up.
The Archive of Our Own implemented a choice of warnings for Rape/Non-Con, Graphic Violence, Major Character Death or Underage, and added a "Choose Not To Warn" option. This enables authors who do not wish to warn for their fanworks to do so, while allowing readers to avoid works which may contain disturbing elements.
Sometimes warnings are used to attract readers who may be seeking a specific type of content, such as a particular kink. Warnings may also be used in a facetious manner, to "warn" readers about content that is unlikely to be disturbing. ("Warnings: You cannot look away from the Shiba Inu puppy cam." .)
Many labels are not warnings, but simply ways to explain the content of the fanwork, such as pairings, timelines, genre, and other assumed non-controversial information.
Warnings and Different FandomsThe Sentinel slash fiction developed a growing list of warnings. The trend peaked in late 1999 or early 2000, when during a Senad discussion about warnings -- with many people suggesting things that should be warned for -- one fan asked that people warn for stories where Blair Sandburg cuts his hair 
In Lord of the Rings fandom, interspecies sex between hobbits and humans is often considered to merit a warning, while many other fandoms consider consensual interspecies sex to be no different from any other, or adequately addressed by pairing tags.
The History of Warnings
For many decades during the print fanfic days, the use of warnings was not commonplace. This is, however, not to say fanzine publishers did not include descriptions in their zine flyers or ads. And one function of fanzine reviews was to offer other readers insight into the fanzine topics before having to part with cash to buy the zine.
In 1987, there was flurry of discussion regarding the labeling of fic, along with warnings. Maggie Nowakowska wrote:When I first found slash fandom, "warnings" were both a signal to other slash fen that there was What We Were Looking For inside those covers, and something to shield us from those manic anti-slash fans going "I READ THIS STORY WHERE SPOCK AND KIRK WERE LOVERS OMG I NEARLY THREW UP!" This was in 1983.
(Also, the "over-18" requirement was fairly serious - as one editor noted to me, when I confessed to having sent her a slightly inaccurate declaration of age (I was 17: she wanted over-21) the first time I bought one of her zines, the reason she asked for age statements was so that if angry parents contacted her, she could show them the age statement their innocent flower had sent the editor: "hey: your kid told me she was over 21, not my fault!")And, to the best of my knowledge, that remained the chief purpose of "warnings" and "age statements" for the next twenty years. The first time I saw "warnings" more complicated than "Slash pairing" was sometime early on in the 21st century, I'm pretty certain. I've published stories before that in zines in which a major character is raped or dies, without a warning being called for or absence of complained about. 
Fans began to want more information about what it was they were buying and viewing; the rise of the age statement is in some ways, was also the rise of warnings and labeling. This comment is from 1988:[regarding Carolyn G's] comment that fan fiction should be able to embrace genres as pro fiction does. For myself, I have long wished stories were identified as "action/adventure", "relationship", "wish fulfillment", etc. The subject came up year ago when "/" stories began to appear regularly, but it got lost in accusations of "censorship" because of the subject material. People who wanted "/" stories identified as such were subject to all kinds of accusations. However, with the changing times, "/" stories tend to be so identified these days. It would be nice if we also had some way of knowing which other "genre" a zine's stories tended to be; or if a zine were fairly well represented, which stories were which. It certainly would help when buying the zines blind, as many of us who don't regularly get to cons (or go at all) must do through the mails. (Yes, there's the good chance that a person will miss a story that's really good in a genre she doesn't usually buy, but good stories tend to get talked about and she can look it up among her friends. Meanwhile, she won't have spent more money than she can afford on zines that aren't really interesting to her. Some people like any story with SW characters in it; some prefer to stay away from fandom's version of, oh, say, bodice rippers; some don't want death stories, or violent stories, etc.) Hey, I can see it now -- international fanlit label! 
In 1988, the editorial of As I Do Thee #11 by Dovya Blacque used the term to avoid "surprises":Age statements serve two main purposes. First, they act as insurance for the publisher. In the fabled case of a litigious parent discovering her minor child reading a zine she feels to be pornographic, the existence of that signed age statement offers a first line of defense. Of course 'literary worth' is the main defense against charges of being pornographic, and I'm sure all fan publishers feel what they are printing has value or they would have rejected it to begin with, but realistically, how many would look forward to having to prove that point in court? Which means that for this purpose whether to require an age statement depends on how fearful the publisher is and how she feels about her zine. Just how 'sexy' or 'likely to arouse prurient interests' or "obscene" (depending on one's attitude towards erotica) does she think it is? Given that homophobia is as common as it is, a parent is more likely to be upset by a line such … Kirk's penis being caressed if the partner is Spock rather than Uhura, so probably for the protection of the publisher the 'explicit-ness threshold' should be lower for K/S zines. to serve as a warning flag to prospective buyers, and this is where I feel today's practice is inadequate. If this purchase will be my first exposure to Publisher A's zines, how can I know if her standards mesh with mine? The fact that she's asking for an age statement implies that she thinks some people may be offended by some of the contents, but what yardstick is she applying—and to what type of content? Is the only problem some "blue" language? Nude illustrations? Are there explicit sex scenes? Is there detailed, gory violence? The same person's taste for, and ability to stomach, differing aspects of "adultness" can vary greatly. For example, "language" doesn't bother me and I consider most art and "sex scenes" to be as big a plus as almonds on a Hershey bar, but not those involving sadistically inflicted pain or the rape of a child, and prolonged descriptions of violence or suffering of any type repulses or depresses me. There is no way the publisher can be expected to know my tastes in that detail. But I do. And if she would only offer enough useful information in her flyer her public would be happy to make their own informed decisions. I appreciate that space is limited in adzines but surely In a full page flyer the publisher needn't hide behind that coy-but-useless "age statement required." If you think some readers might have problems with some of your contents, tell them why. "Adult language used." "Some stories in this zine include explicit torture." Or "one of the stories involves incest." Or pedophilia or cannibalism or sadism or necrophilia or whatever you believe might especially upset a reader. I'm sure the publisher would prefer losing the sale of one particular issue to having a disgusted reader who will never order another zine from her, and who might even "bad mouth" the publisher's works in private or public forums.... I'd have been much less upset by the stories involving zoophilia and sexual torture if I hadn't stumbled into them unwarned.
In 1994 Rachel Sabotini recalled:...I am relaxing my editorial policy slightly. Basically, that means that I will consider publishing a story that is not all sweetness and light if it's an exceptional story. Of course, if I do print anything that is drastically out of the usual for AIDT, there will be a warning to the readers in the editorial. I won't be springing anymore surprises on you!
CI5 mailing list received private complaints from listmembers that a death story posted to the mailing list had not been properly labeled. She observed that she had thought it was the norm to say if a story involved death, but then realised to her surprise that maybe labeling was only common to the Pros online circuit library. This led to a revision of mailing list rules:To hop on an old bandwagon, at my first slashcon, [Koon-tu-Kalicon (in 1989) I, Sandy, the woman who edited The Paladin's Affair (who's name escapes me right now), and I discussed the 'warnings' that she listed on the table of contents of her zines. (I'm one of those people who don't want to know it's a death story because, in general, I like death stories and enjoy the 'will-he' or 'won't he' live thing.)
Basically, we came to the conclusion that it might be nice to put this information on the back page of the zine, where those who like to turn to the last page could find it, while others wouldn't be bothered by the information.All of this, of course, ignores one of the problems I have with labeling: the difference between s/m and h/c, not to mention how to label hurt/hurt stories where there's little if any comfort involved. Come up with some good, non-subjective rules for that and I'll be happy. 
Any story involving the death (beforehand or during) of one of the three main characters must be clearly labelled as a death story in either the subject line and/or the body of the message before the story begins. In a side note, it'd probably be nice if you mentioned who it is that dies, but I won't require that, since it seems it's more the idea of death stories that upsets people, rather than the identity of the deceased. It might also be best for some folks if you mentioned killing off any recurring character, like say Murphy or Susan, but I won't require it. 
By 1998 it appeared that more and more fans expected their online stories to come with warnings:
By 1999, more and more fanfiction had been posted to the Internet with warnings, so that when netfans did come across print fanzines, their lack of warnings often resulted in outrage and cognitive dissonance. In a comment left on Sandy Herrold's rapefic rec website, one fan wrote:i DO NOT read character death. i DO NOT read slash. perhaps authors do not OWE others an indication of classification, but i look at it as a courtesy. a simple courtesy to those for whom you are supposedly posting. frankly, i have enough stress and frustration in my life that i look at atxc as a wonderful release and escape. i don't appreciate being 'tricked' (my word for my perception of the situation, not indicative of the authors' intent). i also have almost no time whatsoever to read and hence use the classifications as a means of screening. i do not read anything that doesn't have a summary or classification. authors can do what they want, i agree, but i still believe it a common courtesy to label character death and slash, if nothing else, since there are so many who feel so strongly about it. 
In response to this complaint about the lack of warnings in fanzines, one fan commented:I *HATED* the PROS zine 'Angel in the Dark' by Thomas: In this one, Bodie is a really sadistic person who keeps playing mindfuck games with Doyle. When Doyle finds Bodie cheating on him with another woman and later confronts him, Bodie rapes him. Then Doyle demands that they end their relationship and threatens to leave their CI5 partnership unless it's over. Bodie reluctantly agrees, but then is killed in a shoot-out a few months later. As he dies, he tells Doyle that despite everything, he really loved him and just couldn't say it.
In shock at this revelation, Doyle kills himself after Bodie dies in his arms. Partner rape; Death story; Suicide. NOT MY THING! But I understand a lot of people loved it. The drawings by Suzan Lovett *were* gorgeous, I must admit.
As I've said to [other fans], there are many stories that I don't like personally, and don't want to read, but I strongly respect the right for them to be posted to story lists/web archives, as long as proper warnings are attached. IDIC, YMMV, etc.I think that's why 'Angel in the Dark' so upset me - there were *no* warnings at all, and you were expecting this beautiful love story, with the gorgeous drawings and title, and it was so explosively violent and horrifying. I hated that more than the story. IF there had been a warning on the first page about partner rape and death story, I wouldn't have had a problem with it.
A fan in 2000 wrote:
I wish you wouldn't [feel you need to include a warning]. It totally telegraphs everything significant about your story and effectively castrates it. Not only does it take all the power out of your work by completely destroying the element of surprise -- the major reason we read -- it gives a totally false impression of what the work contains. Your work is about so much more than the brutally terse, completely unnecessary warning you put on it. There is nothing you've ever written that requires a warning. I've had to stop reading stories with any warning other than "slash" on it, since the warnings destroy any plot tension that might have occurred. Since I already know what's coming, and punch the story might have had is chopped off at the knees! Stop hamstringing your work.... I decided not to send a much longer rant on this topic, but maybe I should send it. I don't want to think that ThePits is going to become yet another forum where I am "protected" from fiction. Other fans attempted to answer the question as to why fanzines lacked the 'necessary' warnings more seriously. 
In 2001 when a fan asked: "I've noticed that zine stories (at least in my experience) don't include the codes and ratings and warnings one usually finds in an online story... even when they contain things that might bother a reader (ranging from AU scenarios to slavery or pedophilia.) They start with the title and author, and that's it; there isn't even a summary, and any notes are at the end. Why is this? To save space? Or because printed books don't include them?" answers ranged from "it is not the zine tradition" to online warnings were needed to avoid "potential liability and prevent people from stumbling upon these stories unaware."
Two fans in 2010 talked of warnings: "We didn't need warnings in those days - it was either slash or it wasn't! It's only now that there's much more slash available that subtle differences of taste have crept in; then, we were grateful for whatever we could find - and just skimmed over the bits we didn't like!  Another an answers: "Gah. I doubt I would have made it then; I'm far too sensitive about things like rape to even consider reading a fic that contains explicit non-con. 
The warnings debate continues across many platforms such as tumblr. Because of the migratory and segregated nature of fandom, the history of warnings and the role they play in fandom is often overlooked. In 2012, one tumblr fan attempted to educate her followers with her own cautionary warning about warnings:
"So, because [the warnings debate] hit pretty much every single fandom I was involved in back in 2009 and I am not sure how aware everyone on Tumblr is about the great debate over the use of warnings in fic, I am going to link you to the following, with the caveat that it does speak about upsetting content in stories, especially about dub/non-con, so if it will upset you, please be aware, however if you can read any of the following links, please do, if only to understand where fandom has been in order to understand how some are expected to be aware of how to use fandom today, and how trigger warning became a far more mainstream term: Fandom Warnings Wank: A Comprehensive Linkspam....[snip] 
Slash fansites in the 1990s and 2000s usually had warning pages for slash content.
Warnings are often the subject of controversy. Some fans choose not to include warnings on their fanworks because they want their work received without preconceived ideas; additionally, warnings may spoil important plot points.A fan comments:
I'm a dinosaur, and I don't believe in warnings so that readers are never exposed to something new, or something that will make them feel. Take a chance, and experience the stories as they were meant to be experienced - without warning, raw, and real. Think of it as the organic form of fan fiction -no artificial additives! 
However, other fans may become mentally or emotionally distraught if they read or view work that contains triggering themes, or encounter a story element that they strongly dislike, and prefer extensive Trigger Warnings. From one fan in 2011:
Another fan in 2013 wrote:I began this post on the suggestion of a friend, who pointed out that people did not seem to understand that survivors (and not just survivors of sexual assault; the bare bones of what I've said, the helplessness you feel upon being triggered and the mental effects of the triggers itself, are often similar across the board) are not just asking for warnings to be saved a mild inconvenience or short-term disturbance. Additionally, survivors are not asking for extensive warnings on their rare and/or particularly specialized squicks. Survivors are asking that authors not hurt them even further by placing them in danger of being thrown back to such harmful mindsets. Survivors are asking that they be given a tool that helps them choose their fandom space and continue to heal, rather than have the same wounds reopened. And most importantly, survivors are asking for something that they did not have at the time of the assault(s): the power to say no. The power to not be made helpless and afraid. 
Comments from a fan in 2015:
- In days of old,
- When zines were bold,
- Nobody did any labeling.
Sorry, just continually shocked when looking through both old zines ... and old online archives of zine stuff. Sometimes they don't even lable the pairing!* (i'm especially bitter after reading a (still pretty good) fifteen chapter epic of angst, tears, hugs in the rain, professions of love, and an eventual reconciliation. Then in the last three paragraphs what i thought was a slash pairing talk about how one is thinking of marrying his girlfriend and having the other as godfather of his many potential children!]
And you can go whistle for a summary.
I feel a great respect for the Fen of old, taking their figurative lives in their literary hands when they bought a zine. In the same way i feel respect for all my ancestors who lived before indoor plumbing, and hot water on tap.
On the other hand, surely the briefest of summaries wouldn't've been too much to ask for? Just a hint of pairing, rating, or genre? Is this 900 pages of torture recovery, or three pages of shaggy dog story?Say what you like about over-zealous trigger warnings; it's better than a complete surprise. 
I actually stopped writing Pros because of attacks about my stories or my desire for warnings on fic. Some earlier fen could be quite aggressive in their opinions, especially if you wrote Bodie/Cowley instead of their OTP.
I think now that I'm older and having been in other, more welcoming fandoms, I might have handled the Pros comments with more grace than I did then. I do think things are calmer and much more inviting than they used to be.... I'm a strong believer in warnings, but in the days of zines, that was difficult to do.
When Pros moved online, I pushed to have warnings in place for stories, but was shot down by most of the big talkers in the fandom. They used the same argument, that it was a spoiler for the story.AO3 is relatively new and I think we sometimes take it for granted. I like having the option not to warn, so that if I see that on a story, I'm reading at my own risk. The idea that every story has no warnings makes reading like walking in a mine field. That's especially true when you have issues with certain kinds of stories like death, mpreg, or any other kind of story that is common in the fandom. I know I once got trounced in Sentinel for not putting a rape warning on a story, but that was an oversight I never did again. 
Disagreement About Content Requiring WarningsThere is perennial disagreement among fans about what kinds of content should be warned for. Warning for certain elements, such as slash, may be seen as homophobic; warning for het, especially when the heterosexual pairing in question is canonical may be seen as misogynistic. Some fans feel that warning for elements that are present in the source text, such as violence, is unnecessary. Some warnings may not have solid definitions shared by all fans; the dub-con label was created in order to address a certain type of rapefic kink, usually along the lines of sex pollen or Aliens Made Them Do It, but some fans debate that there is any difference between rape and dub-con, and there have been instances where fans felt misled by these warnings.
Seriously, let's nail down a precise definition of "rape" and "non-con" (in between sessions of herding cats) and THEN let's talk about whether you should use those warnings or not, because even if everyone started using those warnings tomorrow, everyone would be using them to *mean different things*. .... Like I said to darthhellokitty, even with something as common as being a vegetarian, there will always be people who are like 'Since you're a vegetarian, tonight we're having fish!' 
Some fans feel that having to add labels and warnings to story requires the writer to not only read minds of their readers, but also sets that author up for being accused of trickery: From an X-Files fan in 2000:"Well, I haven't seen American Beauty so I can't speak to it...but let's take another example, the movie Bonnie and Clyde. It's historical fact that Bonnie and Clyde were shot to death by the police, so you pretty much know what will happen to Warren Beatty and Faye Dunaway as soon as you step into the theater. You've been warned. On the other hand, the manner in which they die, and the way it's filmed (long, drawn-out machine-gun fire, bullets being pumped into Bonnie's clearly dead body clearly for the hell of it) may squick you in a way that the *idea* of their death may not. So--what good might that putative "warning" really do? Or Chinatown--you may know upfront that John Huston's character has raped his daughter, but you may not know he's going to walk away being handed his *granddaughter* for the same nefarious purposes--so what if you're not squicked by Incest Situation A, and you *are* by Incest Situation B? Again, what good did your upfront "warning" really do? In which case...should you even bother with "warnings" at all, and on what level?
And for that matter, how exactly can we separate what something is "about" from its essential meaning? Is that even possible?.........how do you factor in context and presentation of theme?....All I'm saying is that "reasonable expectation" [of being warned against triggering content] is one of those notoriously, well, *reasonable*-sounding phrases that people can argue over forever and a day and never come to a clear definition of."
...I can say that the keyword thing becomes a big angsty deal for ME because readers feel the right to publicly call authors "liars" when those authors don't fulfill all their keywording dreams. If the word "liar" isn't used outright, then all the euphemisms for "liar" are used instead: "misled," "manipulated," "tricked." All those things imply that the author did something morally wrong by not meeting the reader's personal list of criteria for headings. There's also generally some hint that the reader has been "damaged" by having to wade through a story that didn't turn out exactly as he expected. 
Writers who do not like to warn are often accused of trying to force readers to read the way they want them to. However, it is not actually possible for a writer to force a reader to read a story without warnings. Since this is the case, most writers who do not include warnings frame the discussion in terms of personal responsibility, arguing that readers who know that they are vulnerable to being seriously affected by certain story elements should refrain from reading unlabeled stories, just as a vegetarian might refrain from eating an unlabeled food product.
In most cases it's just that they themselves do not like warnings as readers, and thus when faced with two types of readers, unsurprisingly favor those like themselves.
There also have been various compromise solutions implemented to satisfy both pro-warning and anti-warning preferences and leave the choice to the readers themselves. That includes special formatting, such as warning display options in archives, putting warnings in a separate post on lists, in a hidden section that is only visible when highlighted in journal or website posts, or on the bottom of the story or linked on a separate page.
Warnings on Songvids
The idea of placing warnings on songvids comes up from time to time. With songvids at convention vidshows, viewers are sitting in a room watching premiereing or new-to-them vids. Some vid shows hand out playlists to the audience, but the playlist can be minimal offering only the fandom, the title of the song and the name of the vidder. Thus, when something squicky unexpectedly appears, the audience is not in the position to change the channel or even easily leave the room.
In the pre-digital age, vid shows were not curated. Vids were handed in on videotapes at the convention and they were played straight through. All the vids by one vidder or vid group were watched together and then the next videotape was inserted into the VCR. Thus, early vidshows had no warnings or playlists. In the 1990s, one convention, Mediawest] began segregating slash fanvids from het and gen fan vids as a primitive method of allowing audience members to choose what type of vids to watch. Even at slash only conventions, where viewers knew what to expect (slashy vids), audiences could be startled by the content of the vids. In the late '80s-early '90s, a few slash vids had m/m porn clips cut into them, which shocked (or at least surprised) some congoers. However it wasn't until 2000 when attendees of vidshow began to demand warnings on the content of the vidshows. For example, during one Escapade vid show, an Oz vid Prison Sex disturbed some viewers with its canonical images of graphic violence. This led a few attendees to complain and later demand warnings on Escapade vidshows. It was the first time this had been requested and signaled a shift in the expectations of the viewing audience towards a more controllable and individual customized viewing experience. While media vidshows had always included movie vids which had R (and in some cases X) ratings, the majority of footage had come from primetime TV shows which were restricted by censors in terms of both sex and violence. Cable TV had however, by 2000 made significant inroads in both, and the request for warnings on vidshows illustrated that not all fans were prepared for fandom to adapt to the increased explicitness in TV and movies. Escapade eventually decided to not include warnings on their vidshows deciding that since the convention was for fans 18 years or older, that this was not necessary.
More recently, vids done to movies (like Absolutedestiny's 15 vid Deep Kick at Escapade 2008 or HBO/Showtime shows with visceral violence (Oz at VividCon 2004, Dexter at Vividcon 2008, have led some congoers to wonder if there is some way to warn susceptible members of the audience before a vid show.
In 2010, some fans began advocating that all vid shows include warnings in advance. (See Vividcon 2010 for a summary of those discussions). Even so, many vidders and attendees found the concept of songvid warnings challenging, as it made it difficult for convention organizers to find an acceptable compromise for attendees. And some conventions, like Vividcon and VidUKon, which host multiple vid shows over an extended three day period have greater logistical difficulties to overcome. The typical fan run convention will only offer one vid show lasting between one to two hours.
Vid show practices also vary across genres. For example, anime vid shows are less submission based and more like contests. Not all vids entered will be shown and there are often multiple rounds of pre-screening. This means that the convention organizers pre-select the content they feel is suitable for their event. And, some anime events are clearly targeted at the PG13 audience while others try to straddle both child friendly and adult fare (with varying degrees of success). However, because of the pre-selection and screening, no warnings or content notices are provided to the audience.
In the context of Yaoi Con (m/m anime), extreme violence is only OK if it fits within the theme of the year. Also explicit m/m is OK, but m/f and femmeslash is not.However, more recently some anime conventions began trying to enforce their PG13 content restrictions as a mean of limiting their liability. At Katsucon 2014, the vid show organizers were unexpectedly hit with violence and sexual restrictions that eliminated many vids. This is what one of the vid show coordinators had to say:
Others point out that while it is perfectly fine for a convention to limit itself to PG13 material - but it needs to be enforced equitably. In fact, oftentimes more explicit content is allowed in the Cosplay/Costume contest, dealer's room and in the anime episodes being shown in the video room.  This double standard is perhaps best reflected in the snarky warning provided by one anime vid show coordinator, even while acknowledging and listing the vids he had to exclude for profanity and sexual content:"We've never had to deal with this kind of thing before now so it's new to us as a department as well.
This con is skittish about protecting their event from any threat of lawsuit, be it concerns over copyright / licensing or psychological / emotional damage or whatever. It feels to me like the walls used to protect also imprison. I almost gave up conventions altogether last night but I can't affect anything from the outside.Last night's meeting was one of the most deflating experiences of my life...seriously"
The N2U 2011 AMV Contest contains: Plot spoilers, good and bad music (which is subjective, anyway), brief strobing effects, mass destruction, girls, girls, girls! (oh, yeah, and some guys), acrobatic dancing, big eff-off swords, a load of balls, a flock of panties, the Overfiend's house plants, about half a bucket of tears, ninja AND pirates and tips about how to survive a zombie apocalypse.Enjoy the show."
With convention attendance on the wane, the number of vid shows have declined, so there are fewer opportunities for fans to watch vids live. As of 2014, the following vid shows are still active. Note that convention practices are in flux and can and will be changed over time and in many case informal warnings are often provided by fellow attendees or upon request.
- Escapade - no warnings
- Con.txt - two playlists are made available in advance, one with warnings and one without. Items warned for: "blood, torture, self harm, suicide, violent religious imagery, abusive relationship, sexualized violence, consent issues, incest, underage, parental homophobia, transphobia, institutionalization, Holocaust imagery, misogynist lyrics, strobing/flashing lights, and sudden volume changesCollapse."
- Mediawest - no warnings, but slash and gen/het vids are still separated
- Muskrat Jamboree - in 2013, warned for one vid; otherwise no formal warning policy.
- Katsucon - no warnings, but anime vids are pre-screened and limited to PG content: "This contest will be viewed by a general audience (all-ages) so try and maintain a PG-rating. Absolutely NO sexual content (this should be obvious), excessive violence (disembowelments, organs, amputations, etc), or profanity will be permitted. Anything that is questionable will be shown to both the judging panel and convention chair for further review. Bottom line: the convention chair has the FINAL WORD!"
- Kiscon - no warnings
- Pacificon - content notes and warnings supplied via LJ in advance
- Revelcon - no warnings
- Sharecon - no warnings
- Southern Media Con - no warnings
- Wincon - no warnings made in advance
- Wiscon - TBA
- VidUKon - vidders and VJs are asked to submit warnings with their vids; however, warnings are not mandatory (vidders and VJ may state "Choose not to warn" on all of their vids). Attendees may contact the concom with requests for specific warnings; anonymous email contacts permitted. Collected content info included in the attendee registration packs.
- Vividcon - - vidders and VJs are allowed to submit warnings with their vids; however, warnings are not mandatory (vidders and VJ may state "Choose not to warn" or simply not provide any information at all). Attendees may contact the concom with requests for specific warnings; anonymous email contacts permitted. Note: in 2014, Vividcon limited the number of shows available for private warnings to premiering and/or new vids.
- Yaoi Con - no warnings, however extreme violence may not be accepted unless it fits within the annual vid show theme. Het and femmeslash content not accepted. Explicit adult material (m/m) accepted. 
Interestingly, a few conventions such as Vividcon and VidUKon have begun experimenting with streaming their vids shows during the convention to a wider online audience. Most vidshows, have up to this date, relied on providing play lists with links to the vidder's own streaming version after the convention has concluded for those fans unable to attend the event live. How these practices will change - if any - the existing warnings policies is unknown. However, as some have argued, the streaming viewing experience is different than the live viewing experience and warnings policies for streaming vids tend to be left to individual vidders who have adopted a wide and diverse range of approaches (see section below).
Warnings on vids that are streamed online depend on the preferences of the vidder and the fandom culture. For some vidders it seems natural to include the same types of warnings they would on fanfic. And, since vids are a visual medium, a few vidders will include warnings on flashing lights and quick edits as these have the potential to physically impact viewers. But unlike vidshows which are a compilation of various vids shown live, vidders own their own websites and blogs and have greater control over whether to warn or not. And most of fandom seems content to allow them to exercise that control. As one fan explained it: "I don't get warnings on some of the crap I see on Youtube. Why should I expect warnings on fanvids?" (cite source?) Other fans feel that this is not accurate as Youtube uses flags to allow viewers to demand removal of objectionable content. However, allowing fans to demand removal of fanfic, vids, and art raises a whole other set of issues in the warning debates.
The Archive of Our Own allows vidders to embed their vids and use the existing fanfiction warning structure for fanvids. In that case, vidders can warn along a specfic set of criteria, create custom warnings or "choose not to warn".
For vids created as part of an organized community challenge or gift exchange, the warnings practices vary. For example, vids created as part of the Supernatural Big Bang are required to be rated according to the US movie rating system (G, PG13, R, X etc). A standard template must be used, but the "Warnings" line can be deleted if "not applicable" and there are no guidelines as to what, if any, to warn for. Fans can add whatever warnings they like on the entries posted in their blog - the challenge rules only apply to the links posted to the challenge community.
Vids created as part of Festivids do not carry mandatory warnings but do have to comply with standardized content notes.
"All vids are required to pick one (possibly more) of the following standardized content notes:
- No standardized notes apply
- I prefer not to give content notes (viewer proceeds at their own risk: could be anything)
- Sexual violence
- Physical triggers (e.g. epilepsy or migraine: strobe lights, bright lights, "stuttery" cuts between 2-3 stills)
- Other (you may use this box if you would like to indicate the presence of other content, such as, for example, particularly graphic violence, self-harm, or anything else)"
On The Challenges of Crafting Warning Standards
In response, Cybel Harper offered her thoughts on the proliferation of types of warnings:"As to marking, I do like knowing if it is a death story because I tend to avoid those. So many are over-the-top sentimental in a cliched sort of way. There are good ones - Endgame, for example, and The Last Time We Saw Bodie - wrenching, but good in the standard loose use of the word.
Marking for s&m content is probably a good idea too, since many people seem to want to avoid those stories. So marking for certain kinds of content might be worthwhile.But it is impossible to classify every story, and many people would argue about certain classifications, so people are just going to have to read the stories to see what they are in many cases. If it is in my house I'm probably going to read it at some time or other.
In 2000, a fan wrote of the difficulties of writing summaries:There used to be only a couple of 'types' of slash that seemed to upset some fans and that were sometimes labeled due to that fact, mostly death stories and, maybe, S&M. I'm sure others would add categories such as graphic violence, partner rape (or rape in general) etc.
These are problematical categories that push some very intense cultural, personal, and perhaps even ethical buttons. I'd hate to think that we need to categorize *all* stories based on every other like/dislike among fans. Talk about cutting off our noses despite our faces!
I, and, I'm sure, many other fans like some graphic sex scenes, and not others. Like some PWPs and not others. Like some well written stories, and not others. Hell, I even have liked *some* rape stories (damn few, though) and a death story or two, and at least one B7 story about Blake as a pedophile (thanks a lot, MFae, I used to be a nice Catholic girl!).
Some fans are wonderful story tellers, but not particularly good writers.
Some of their stories are unreadable, others are lovely. And yes, I am a grammar and typo and quality freak, but I can still like a given story based on other merits as well. I've even read some *gasp* GEN stories that I've loved!
Um, back to my original point.We can categorize ourselves to death, I think. No matter how a story is labeled, I prefer to give it a chance and decide on its relative merits myself. Labels might protect me from an occasional bad (or boring) experience, but they might also influence me to skip stories I would love if I gave myself the chance to read them. And if I'm going to at least *try* to read them, why do I need a label? 
In 1994, alexfandra offered her tongue-in-cheek take on the difficulty of coming up with a standardized set of warnings (or as the terminology of the time, a 'story marker'):And what about the people who want to know *something* about the story but not *everything?* It doesn't have to be an all or nothing thing. I like headers; I read them before I read a story I like to have a general idea. I *don't* always appreciate the entire story spoiled. The reason it is best that headers are left completely up to writer is because he or she knows his/her story best; and which headers will tantalize and which headers will totally spoil the story. It's a bit like the previews for the episodes in a sense. You might claim the episode preview for "Pusher" was "incomplete" when it showed Mulder pointing his gun at Scully. Perhaps you would have preferred the announcer disclaim the scene by saying "Yes, that's Mulder pointing a gun at Scully; but the villain is using mind control in this episode. Oh, and he doesn't end up shooting her in the end. She throws the fire alarm to distract the villain; and both Mulder and Scully survive to see their next case." This is what you are asking the writer of a story to do when you criticize her headers as being incomplete. I have actually seen headers/summaries that are written like this: "This story has a M/O in it. But don't worry shippers, the Other turns out to be a real bitch, Scully sends her packing, and Mulder and Scully get together in the end. I promise! Please, please don't turn away from my story." In the less extreme version, you have: "M/S UST then M/O then finally MSR." The latter of course is more common, less words more initials; but still spoils the story just as well in its "completeness." 
Well, many of you know how picky I am...see, if I have no clue what the story is, this is what I do: go straight to the end page, skim the last few paragraphs to make sure it a) isn't a death story and b) has a happy ending. Then I flip through the rest of the pages to make sure that neither Bodie nor Doyle is spending all of his time with Murphy. Then I actually read it.
As someone pointed out, some type of story marker is very helpful when ordering long stories from the circuit library, sight unseen. I DO NOT DO DEATH STORIES, PERIOD. Don't care if they were written by the slash equivalent of Dostoevsky. NO. NEVER. WILL NOT CROSS MY THRESHOLD. AND THAT'S FINAL. In regards to the Thread Next Door, I do wish that the library marked first-person stories, 'cause I'm one of those fans who can't stand 'em. But then, I don't generally like them in non-slash fiction, either. Too much time spent inside one person's head makes me feel claustrophobic. Or something.
This seems like a good time to repost my list of Things in Pros Fanfic That Shouldn't Make Their Way Into My Life, or:
- Just Say No
- No death stories. No Bodie/Cowley. No Bodie/Murphy. No Doyle/Murphy. No Cowley/Murphy. No Bodie/Cowley/Murphy. No elves. No werewolves. No vampires. No centaurs. No sheep. No sex with teddy bears. No first person. No embarrassing sex scenes in public. No "Let's get married". No "Let's quit CI5 and set up house in the country and raise Irish Wolfhounds." No "Let's quit CI5 and set up house in the country and raise horses." No "Let's quit CI5 and become a musical duo." No Doyle-is-forced-to-be-a-sex-slave-in-a-leather-bar. No "It's ten years later and we must now discuss STDs, gays in the military, condoms, and other issues of serious import". No Doyle in drag. No Bodie in drag. Cowley can be in drag. So can Murphy. But only if it's a Cowley/Murphy story. No anal plugs. No Cowley/Murphy stories. No excessive nipple sucking. No humiliation, unless you're Sebastian and can write something as good as "On Heat". No Mysterious Illnesses which May or May Not Be Terminal. No excessive licking of ears. No "turgid members". No "manhoods". No "he was tight and hot like a virgin". No "then Doyle dipped his fingers in the pool of Bodie's cum on his chest, licked it a little, and then held his fingers to Bodie's lips and Bodie sucked them, murmuring sweet words of love". No margarine. Story markers are great, but they just aren't detailed enough for me, I guess.
And finally, as some fans point out, warnings lack the necessary nuances to convey the true nature of some fanfic: "Personally, I don't like to see stories pigeon-holed so cavalierly .... A story could be brilliantly written, insightful, compelling, fresh, but if a character dies -- bang -- it is a "death" story."
- (2002) Story Warnings: Please be advised there is adult content in this story. By adult content, I mean content that would be defined as 'adult.' Sex is conspicuous throughout the story (I'm sure most of you will reconize it.) so when you come to a segment that contains sex, the section will be highlighted by the words 'BEGIN SEX.' When that section is over, the words, 'END SEX' will appear. Readers not sexual by nature should make note of this and skip over any sections that begin and end. Readers who have any sexual preferences to their aversions must make the folowing distinctions: 'NS' indicates a 'Normal Sex' scene. 'KS' refers to a 'Kinky Sex' scene. Please do not confuse the two terms... This is a death story, by which I mean the word 'death' does appear and is used in its proper context. Just as sex segments are marked with sexual warnings, death segments will be marked with deathly warnings... This is an AU story. However, since I don't know what an AU is, I can only warn readers not to read this story if they are unfairly and ignorantly biased against AUs... There are some bad words in this story. (However, please know that I had a friend add these bad words, as I would never use them myself.)... 
- (2007) Dear World: re: gen vs. het/slash, warnings, labels, etc. I would like warnings for things I do not like, so that I can avoid them, and labels for things I really like so that I can make gimme hands and pounce on them immediately. I would like no warnings or labels at all for things I am neutral or uncertain about so that I can just enjoy the fic without any preconceptions. Stories with minimal romantic content are gen unless I dislike the pairing you've chosen, in which case they cease to be gen and require a warning (see above). Now just make sure that your hundreds of potential readers all like and dislike the exact same things, and you're golden. Thanks! *blows kisses* 
- New change to the AO3’s “Archive Warning” system, posted 2009-12-18, accessed 2016-04-20
- Seraphwings,header of fic; WebCite. Accessed November 13, 2008
- See The Fanfic Commenter's Dilemma, Archived version
- A fan in 2009 posted "I don't care that once upon a time someone demanded warnings for cutting Blair Sandburg's hair. In fact, if I never hear another word about Blair Sandburg's goddamn hair, it'll be too soon. It's a straw argument and it's derailing and I'm sick and tired of it." -- I Don't Care Abut Blair Sandburg's Hair; archive link, posted by fairestcat, June 23, 2009. For more context, see Blair's Hair: Warnings.
- Also see comments by ratcreature at Warnings; Archive, post by zvi, June 22, 2009
- Private email sent to Morgan Dawn on Sept 22, 2013, quoted with permission.
- from Jane Carnall at her online journal; WebCite, posted July 2010
- from Southern Enclave #16
- from Treklink #14
- September 1994 post to the Virgule-L mailing list, quoted with permission.
- Morgan Dawn's personal notes, accessed November 3, 2012.
- Morgan Dawn's personal notes accessed November 3, 2012. The rule did not identify the three main characters, but it was generally understood that they were Bodie, Doyle, and Cowley.
- comment by kronos at "A KeyChain in the snow", archive link, December 27, 1998
- Website offline, review accessed via Morgan Dawn's personal notes, November 3, 2012.
- Posted February 1999 to a private mailing list quoted with permission.
- Flamingo's comment on June 25, 2000 to a fan regarding her fiction. The comment was posted on The Pits, a Starsky & Hutch mailing list that required membership and is now offline. These comments are posted on Fanlore with permission from Flamingo.
- Zine Question posted to alt.startrek.creative.erotica.moderated on August 19, 2001.
- from theficklepickle at Epic Recs, May 25, 2010, accessed September 24, 2013
- from janeelliot at Epic Recs, May 25, 2010, accessed September 24, 2013
- WayBack machine link.
- Sunday Morning Fannish History; reference link.
- from  Deb Walsh Classic Genzine Fan Fiction Archive, accessed 7.5.2011
- Fuck Yeah, Trigger Warnings, I Would Like To Talk With Ya'll About Trigger Warnings, accessed July 6, 2011.
- impertinence, Sexual Assault, Triggering, and Warnings: An Essay,archive.is, accessed July 6, 2011
- wellharkerather, October 29, 2013]
- comment by grey853 at The Good Old Days...I've been wondering..., September 12, 2015
- Liviapenn in comments, The warning debate, 2007 edition Posted January 05, 2007. Last accessed November 13, 2008.
- post to the Bindlestitch mailing list dated May 14, 2000, quoted anonymously with permission.
- Kipler, alt.tv.x-files.creative, October 2, 2000
- Elke Tanzer.Gut reactions are visceral, let me show you them. Posted 11 March 2008 (accessed 15 November 2008)
- It should be noted that most convention organizers tend to focus on creating policies for attendees rather than the fan population at large, many of whom have never been nor will ever attend a convention. This fact can be overlooked by those advocating universal warnings.
- Re: KATSUCON 20 AMV Showdown...FINALISTS! dated Feb 2014.
- Re: KATSUCON 20 AMV Showdown...FINALISTS! dated Feb 2014.
- [http://www.animemusicvideos.org/forum/viewtopic.php?f=5&t=107372&p=1413384&hilit=warnings#p1413384 [WINNERS] N2U 2011 AMV Contest] dated Nov 25, 2011.
- Additional info that would be helpful for this section: a list of anime cons that show fanvids and their warnings practices. Commercial, for profit conventions like Creation Con offer some video contests on occasion, "but bans anything controversial outright including slash." (See Moar Vividcon Wank Brewing for the Nonstalgic? dated May 14, 2014; WebCite. Also, most of the TV shows featured at Creation Con events are prime time TV shows.
- 2012 Vid show post.
- March 19, 2013 Vid Post; WebCite.
- 2014 AMV Showdown Contest Rules (accessed May 14, 2014).
- April 2014 vid show announcement.
- Sell all Wincon Vid show posts in their LJ community.
- "In order to make the warnings process more sustainable, starting this year we will be making private warnings available for premiering vids only, instead of for every vid shown in every vidshow at the con, as we have previously attempted to do. Warnings will be available upon request for the following vidshows: Premieres, Non-attending Premieres, Auction, and Challenge. Warnings for premiering vids from Club Vivid, Nearly New, and themed vidshows will also be available, if possible, but they will be a secondary priority behind the premiering vidshows. In addition, warnings requesters will also receive playlists for non-premiering vids and vidshows as soon as they are finalized, to allow the requester time to review, investigate, or have a trusted friend evaluate any unfamiliar non-premiering vids in those vidshows for the requester's warning needs. See Request warnings by June 15th -- new details, please read! dated May 11, 2014; WebCite.
- Yaoicon 2012 Rules post in the animemusicvideos.org forum] dated June 2, 2012.
- How to Post post dated May 13, 2013.
- http://festivids.livejournal.com/profile Festivids Profile Page] (accessed May 14, 2014); WayBack Machine link.
- September 1994 post to the Virgule-L mailing list, quoted anonymously with permission.
- Cybel Harper posting to the Virgule-L mailing list July 1996, quoted with permission.
- Teddi, alt.tv.x-files.creative, November 2, 2001
- Posted September 1994 to the Virgule-L mailing list, quoted with permission.
- September 1994 post to the Virgule-L mailing list, quoted anonymously.
- from the zine, Dangerous Lives, Dangerous Visions #1, by Lizzie Burns
- comment by elz: Well, duh, March 20, 2007