Who Is Anonymous: 10 Key Facts

The Anonymous "hacktivist" collective, known as much for its self-branding as its anything-goes, anti-authoritarian sense of online comeuppance, first came to public attention in January 2008. The occasion was an internal Scientology video starring Tom Cruise, which had been leaked to YouTube. The church, saying that the video was copyrighted, requested that YouTube remove it. Members of Anonymous, however, took issue with that request, and as part of what it dubbed "Project Chanology," reportedly began launching distributed denial-of-service (DDoS) attacks against Scientology websites, blanketing church centers with prank phone calls and faxes, and "doxing" the church by releasing its sensitive documents into the public domain, for example via peer-to-peer networks.

On January 21, 2008, a YouTube post set the template for future Anonymous proclamations. The video, in this case criticizing the Church of Scientology, includes the now-common Anonymous sign-off: "Knowledge is free. We are Anonymous. We are Legion. We do not forgive. We do not forget. Expect us." By the next month, Anonymous claimed that 7,000 people had staged protested outside of Scientology centers around the world, many of them sporting the now-famous, black-and-white Guy Fawkes mask, as worn by the protagonist of the film V for Vendetta to hide his identity. (Notably, in the film, the masses also wore it as they rose up to help overthrow the ruling dictatorship.)

By early 2008, Anonymous--which reportedly grew out of the anarchic 4chan imageboard website--was already pursuing online attacks as a form of nonviolent protest. By 2010, it was launching regular DDoS attacks against pro-copyright websites.

But the group really came to public prominence during its defense of WikiLeaks and its charismatic--if reportedly mercurial--leader, Julian Assange. WikiLeaks, of course, came under fire from the U.S. government after the site obtained video footage from a U.S. helicopter strike in Iraq that killed two Reuters employees, as well as two children. Next, Assange began to coordinate--together with major newspapers in multiple countries--the release of hundreds of thousands of secret U.S. government cables beginning in December 2010.

The government-orchestrated reaction was swift. PayPal and credit-card processors MasterCard and Visa blocked payments to WikiLeaks, which relied on donations to lease server space and pay staff. There's a short lifespan for a whistle-blowing website that can't remain online.

In response, Anonymous mobilized, unleashing its so-called Low Orbit Ion Cannon (LOIC) tool, with which anyone could participate in Anonymous DDoS attacks by lobbing packets at designated website. From there, meanwhile, Anonymous expanded its focus, and backed by what appear to be numerous international chapters, has tackled everything from cartels in Mexico and child pornography file-sharing sites, to takedowns of Israeli government servers and U.S. law enforcement agencies.

Keep reading for a closer look at the group, its offspring organizations, and its infamous hacks. Photo: Anonymous Hollywood Scientology protest, by Jason Scragz, Flickr. Used with permission via a Creative Commons license.