Many people may not know what fanfiction is, and I suspect that some people that might pop into this site, may not even have heard the term "fanfiction" before. Therefore I am so kind as to quote from Wikipedia (any words you don't understand, see my dictionary-page):
Fan fiction or fanfiction, also known as fan fic, fanfic, fic or FF, is fiction written in an amateur capacity by fans as a form of fan labor, unauthorized by, but based on, an existing work of fiction. The author uses copyrighted characters, settings, or other intellectual properties from the original creator(s) as a basis for their writing and can retain the original characters and settings, add their own, or both. Fan fiction ranges in length from a few sentences to novel-length and can be based on fictional and non-fictional media, including novels, movies, comics, television shows, musical groups, cartoons, anime and manga, and video games.
Fan fiction is rarely commissioned or authorized by the original work's creator or publisher or professionally published. It may infringe on the original author's copyright, depending on the jurisdiction and on legal questions, such as whether or not it qualifies as "fair use" (see Legal issues with fan fiction). The attitudes of authors and copyright owners of original works towards fan fiction have ranged from encouragement to indifference or disapproval, and have occasionally responded with legal action.
The term came into use in the 20th century as copyright laws began to distinguish between stories using established characters that were authorized by the copyright holder and those that were not.
Fan fiction is defined by being related to its subject's canonical fictional universe, either staying within those boundaries but not being part of the canon, or being set in an alternative universe. Thus, what is considered "fanon" is separate from canon. Fan fiction is often written and published among fans, and as such does not usually cater to readers without knowledge of the original media.
Definition
The term fan fiction has been used in print as early as 1938; in the earliest known citations, it refers to amateur-written science fiction, as opposed to "pro fiction". The term also appears in the 1944 Fancyclopedia, an encyclopaedia of fandom jargon, in which it is defined as "fiction about fans, or sometimes about pros, and occasionally bringing in some famous characters from [science fiction] stories". It also mentions that the term is "sometimes improperly used to mean fan science fiction; that is, ordinary fantasy published in a fan magazine".
History
Before copyright
Before the adoption of copyright in the modern sense, it was common for authors to copy characters or plots from other works. For instance, Shakespeare's plays Romeo and Juliet, Much Ado About Nothing, Othello, As You Like It and The Winter's Tale were based on recent works by other authors of the time.
In 1614, Alonso Fernández de Avellaneda wrote a sequel to Cervantes' Don Quixote before he had finished and published his own second volume.
Star Trek fandom
The Star Trek fanzine Spockanalia contained the first fan fiction in the modern sense of the term.
The modern phenomenon of fan fiction as an expression of fandom and fan interaction was popularized and defined by the Star Trek fandom and its fanzines, which were published in the 1960s. The first Star Trek fanzine, Spockanalia (1967), contained some fan fiction; many others followed its example. These fanzines were produced using offset printing and mimeography and mailed to other fans or sold at science fiction conventions for a small fee to cover the cost of production. Unlike other aspects of fandom, women were the primary authors of fan fiction; 83% of Star Trek fan fiction authors were female by 1970, and 90% by 1973. One scholar states that fan fiction "fill[s] the need of a mostly female audience for fictional narratives that expand the boundary of the official source products offered on the television and movie screen."
World Wide Web
Fan fiction has become more popular and widespread since the advent of the World Wide Web. According to one estimate, fan fiction comprises one-third of all book-related content on the internet. In addition to traditional fanzines and conventions, Usenet newsgroups and electronic mailing lists were established for fan fiction and fan discussion. Online, searchable archives of fan fiction were also created, with these archives initially being non-commercial hand-tended and specific to a fandom or topic. These archives were followed by non-commercial automated databases. In 1998, the non-profit site FanFiction.Net was launched, which allowed anyone to upload content in any fandom. The ability to self-publish fan fiction in an easily accessible archive that did not require insider knowledge to join, as well as the ability to review stories directly on the site, led the site to quickly gain popularity. A popular example of modern fan fiction is E. L. James's Fifty Shades of Grey, which was originally written as fan fiction for the Twilight series and featured Bella and Edward. To avoid copyright infringement, James changed the characters' names to Ana and Christian for the purposes of her novels, a practice known as 'pulling-to-publish'. Anna Todd's 2013 fan fiction After, about the boy band One Direction, secured a book and movie deal with renamed characters in 2014. A movie adaptation, After, was released on April 12, 2019.
On May 22, 2013, online retailer Amazon launched a new publishing service, Kindle Worlds, which allowed fan fiction of certain licensed media properties to be sold in the Kindle Store, with terms including 35% of net sales for works of 10,000 words or more and 20% for short fiction ranging from 5,000 to 10,000 words. However, this arrangement included restrictions on content, copyright violations, poor document formatting, and use of misleading titles. Amazon shut down Kindle Worlds in August 2018.
Legal issues with fanfiction
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Copyright holders' attitude towards fan fiction
Some copyright holders have stated specific positive or negative attitudes towards fanfiction.
Studios, productions companies, and producers
Most major studios and production companies tolerate fan fiction, and some even encourage it to a certain extent. Paramount Pictures, for example, allowed the production of Star Trek: The New Voyages and Star Trek: The New Voyages 2 from Bantam Books, fan fiction anthologies which followed Bantam's Star Trek Lives! by reprinting stories from various fanzines; as well as Star Trek: Strange New Worlds, a series of ten anthologies from Pocket Books in which the short stories were selected through an open submissions process geared toward novice writers.
Due to the ongoing nature of television production, some television producers have implemented constraints, one example being Babylon 5 creator J. Michael Straczynski. His demand that Babylon 5 fan fiction be clearly labeled or kept off the Internet confined most of the Babylon 5 fan fiction community to mailing lists during the show's initial run.
Many writers and producers state that they do not read fan fiction, citing a fear of being accused of stealing a fan's ideas, but encourage its creation nonetheless. When Buffy the Vampire Slayer went off the air, for instance, creator Joss Whedon encouraged fans to read fan fiction during the show's timeslot.
Authors
While many authors (for example, Neil Gaiman, J.K. Rowling, D.J. MacHale, Stephenie Meyer, and Terry Pratchett) do not take issue with authors of derivative works, a number of authors do. They may request that fan-fiction archival sites remove and ban any pieces of fan fiction based on their original works. To date, no fan fiction archive has failed to comply with an author's request to remove works, and many archives feature a full list of authors whose work cannot be the source of a fan fiction on their site.
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J. K. Rowling has also complained about sexually explicit Harry Potter fan fiction. However, lawyers on behalf of Ms. Rowling specifically noted that she has "no complaint about innocent fan fiction written by genuine Harry Potter fans" and she "is happy for spin-offs to be published online as long as the publications are not sold and it is made clear she was not involved in the stories", under the condition that they do not contain pornography or racism.
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Anne Rice objected to fan fiction based on any of her characters (mostly those from her famous Interview with the Vampire and its sequels in The Vampire Chronicles) or other elements in her books, and she formally requested that FanFiction.Net remove stories featuring her characters. However, in 2012, Metro reported that Rice has taken a milder stance on the issue: "I got upset about 20 years ago because I thought it would block me," she said. "However, it’s been very easy to avoid reading any, so live and let live. If I were a young writer, I’d want to own my own ideas. But maybe fan fiction is a transitional phase: whatever gets you there, gets you there." Similar efforts have also been taken by Annette Curtis Klause, Robin Hobb, George R.R. Martin, and Robin McKinley among others. Many authors do this, they state, in order to protect their copyright and especially to prevent any dilution, saturation, or distortion of the universes and people portrayed in their works.
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Some authors have said that they wrote fan fiction before they were published, or are pro-fan fiction. Naomi Novik has mentioned writing fanfic for television series and movies, and says she'd be thrilled to know that fans were writing fanfic for her series (though she also said she'd be careful not to read any of it); Anne McCaffrey allowed fan fiction, but had a page of rules she expected her fans to follow; Anne Harris has said, "I live for the day my characters get slashed"; Tamora Pierce stated on her website that she began writing The Lord of the Rings and Star Trek fanfiction and has no issue with fanfictions based on her works, provided they are non-profit. Author Cassandra Clare was a popular Harry Potter fanfiction author before she published her first novel.