Archive of Our Own

Archive of Our Own (also known as AO3) is a relatively new Fanfic (along other fanworks like fanarts and podcasts) Web site. The site itself has been running since late 2008, but only started to become widespread and popular from 2011 onward. To give an indication of how young it is compared to the existing behemoth Fanfiction.net, AO3 contains, as of August 2017, 3,229,000 fanworks in total. The Harry Potter fandom on FFN has over 770,000 on its own, and the site in total is estimated to host about 5 million stories. The rise in popularity of AO3 was helped along by the rise of Tumblr, as both sites initially shared a similar fandom mentality and outlook; when the fandom ambient in Tumblr changed on the late 2010's to be more restrictive, AO3 began to serve as a fandom haven.

Part of the reason AO3 has comparatively less fanworks than other sites, even taking account for age and traffic, is because the site only accepts new users by invitation. While nowadays they have an easy button to get one and the queue of acceptation moves quite fast, at the beginning the only way to get an invite was by other user inviting you, and the first users were BNFs. That, and the fact that their initial focus was into backing up fanfic archives in danger, gave the site the reputation of being "elitist" and "full of actually good quality fic". Due to having been funded by survivors of content purges in several other sites (more notoriously the FF.net purge of NC-17 fanfics and LiveJournal's deletion of fandom blogs) Archive of Our Own allows writers to publish any content, so long as it is legal.

The main differentiating features of the site are the "kudos" button (a version of the "likes" in Facebook, except that you don't need to be registered to give one), its "collection" system (that lets the authors link fics together as part of a "series" and to group together fics produced by different authors for particular criteria like fandom events or themed challenges) and its tagging system (very similar to Tumblr's own, and with similar ups and downs). The site encourages users to use the tag system as a complement of Media Classifications, to add content warnings for controversial contents (like "Death of a major character" or "Rape/Non-Com") and so reinforce the informed version of "Don't Like, Don't Read". AO3 also let the authors orphan (i.e. dissociate their name/online identity from) their fanworks and to lock their fics to be viewed only by registered users if they wish to, which serves as an alternative to deleting everything in case the author wants to leave their fandom identity behind. The site has several usability improvements not present in other sites, like providing in-site color schemes designed for easy reading, showing the full fic in a single page instead of chapter by chapter, and downloading the fanfic as an e-book for offline reading.

As of 2017, the most popular fandoms on the site include Haikyuu!! Harry Potter, Homestuck, Supernatural, Doctor Who and its spinoffs, Marvel & The Avengers (mostly centered on the Marvel Cinematic Universe incarnation of the franchise), DCU,  Real Person Fic (usually centered on K-pop bands and One Direction), and Sherlock Holmes (mostly because of popular adaptations like Sherlock).