[[http://archiveofourown.org/ Archive of Our Own]] (also known as [=AO3=]) is a relatively new FanFic Web site. The site itself has been running since late 2008, but only started to become widespread and popular from 2011 onward.

The inception of the Archive started after the decline of {{Livejournal}} as a fanfic hosting platform, especially the notorious Strikethrough '07 incident, where Livejournal responded to threats from a group of trolls purporting to be online vigilantes hunting paedophilic content by deleting a large number of allegedly "objectionable", but in most cases entirely innocent, journals and communities without warning, which resulted in many fans losing the contents of their journals. (Particularly affecting ''Franchise/HarryPotter'' fandom, due to assumptions that any sexually explicit fanworks set in the universe must be "child porn".) [=AO3=] as a project of the Organisation of Transformative Works was a response to this, and the goal of the 'archive of our own' is to ensure a safe archive that would not purge fanworks due to pressure either from MoralGuardians or aggressive copyright enforcers.

To give an indication of how young it is compared to the existing behemoth FanFictionDotNet (which started in 1998), [=AO3=] reached one million stories in total on February 15, 2014. The ''Franchise/HarryPotter'' fandom on FFN had roughly 674,000 on its own on the same day.

The rise in popularity has been helped along by the rise of Website/{{Tumblr}} as both sites share a similar fandom mentality and outlook, as well as by [=AO3=] being the official hosting site or encouraged posting site for a few popular fanfic fests and events such as Yuletide. It also gained popularity when Fanfiction.net had a crackdown on Mature Content Fics in June 2013 (the last time that website did such a crackdown was back in 2002). [=AO3=] is very popular because it allows users to view fics as one single document instead of the separated chapters and even download stories as HTML, EPUB, MOBI and PDF files, making it great for people who want stories on the go.

It also has a ''much'' less restrictive Review system than Fanfiction.net--like Livejournal, it uses comments which may be edited and stacked on at your leisure, rather than having a single use for each chapter that can never be edited, replied to only privately.

Also notable is the "Kudos" system, which allows someone to say that they like the work without going to the trouble of a comment, but still better than another tick on the view count.