Anonymous refers to a loosely connected group of online activists who first emerged in 2003 on the image-sharing site 4chan.

The group, while having many different interests representing the anonymous and decentralized nature of the movement, has supported some common causes in opposing repressive governments and advocating for online privacy.

Anonymous gained more fame in recent years for its conflicts with the Church of Scientology and the Westboro Baptist Church.

The group has many critics, often referring to Anonymous as cyber terrorists, and a number of members have been arrested for piracy and other online offenses.