The 4chan chatroom is created. People used the site to recruit armies of tricksters for elaborate online pranks. The site offers them the option of posting anonymously, they begin to call themselves Anonymous. A culture is born.
The pranks are called "raids," and they often involve ganging up on other Internet users. In one raid that anons would characterize as "epic," anons storm into the online multiplayer video game Habbo Hotel. A year later, on the anniversary of the first raid, they do the same thing all over again.
Anons are mostly about the "lulz," or laughs, until 2008, when they organize an "epic" series of protests of Scientology : what started out as a prank turns more serious as the protests begin to attract earnest critics of Scientology. But many anons disapprove of the serious tone, and a divide opens up in Anonymous people who care about morals ("moralfags") and people who are only in it for the laughs, or "lulz" ("lulzfags").
WikiLeaks and several major media outlets publish a stash of leaked US diplomatic cables. A week later, several-credit card companies say they're cutting off donations to WikiLeaks. Anonymous takes down the websites of Visa and PayPal.
Protests break out in Tunisia, and anons create a chat room where they provide Tunisians with software that can be used to get around the government blocks of the Internet. Activists in the chat room also provide Tunisians with information on treating wounds and broken bones. When the unrest spreads to Egypt in January, Anons expand their field of operations to assist Egyptians.
n the early weeks of the Occupy movement, Anonymous serves as a sort of publicity wing, using its Internet fame to spread word at a time when few traditional media outlets are paying attention. People affiliated with Anonymous also claims credit for digging up and publicizing the personal details of a number of bankers and cops, including Anthony Balogna, the New York police captain who became an inadvertent YouTube villain after firing pepper spray in the faces of two nonviolent female protestors in Manhattan.
Anonymous hackers’ Russian branch has claimed responsibility for shutting down the Kremlin and the Russian President ‘s websites repectively. ‘Russian Anonymous’ had warned they would launch an attack at Russian governmental sites to demonstrate solidarity with the Russian opposition demos.
‘Operation Free Korea" calling for ‘controversial leader Kim Jong-un to resign’, ‘install free democracy’ ‘abandon its nuclear ambitions’ ‘uncensored Internet access’ etc. The hackers also proclaimed that if North Korea do not accede to their demand, they will wage “Cyber War.” On April 3, 2013, hacker group identifying itself as Anonymous claimed it had stolen all 15,000 user passwords as part of a cyberwar against the DPRK. A few days later, Anonymous claimed to have hacked into the Uriminzokkiri main website, and the Twitter and Flickr pages representing the website.
Instead, a picture posted Thursday on the North’s Flickr site shows Kim’s face with a pig-like snout and a drawing of Mickey Mouse on his chest. Underneath, the text reads: “Threatening world peace with ICBMs and Nuclear weapons/Wasting money while his people starve to death.” 
On June 22, 2013, Anonymous claimed that it managed to steal military documents from North Korea, and that the documents would be released on June 25, the day the Korean War started. However, no such documents appear to have been released.
Anonymous posted a video warning to the Ferguson, Missouri, police, admonishing them for fatally shooting Mike Brown, an unarmed African American teenager, and swearing revenge if any protesters demonstrating against the police are harmed. The group, which has adopted the Guy Fawkes mask as its symbol and frequently becomes involved in contentious legal matters, said in the video late Sunday Brown’s death Saturday is just the latest example of police misconduct having deadly consequences
In response to the Charlie Hebdo shooting, the Anonymous released a statement offering condolences to the families affected by it and denounced the attacks as an "in-human assault" on freedom of expression. They also addressed the terrorists: "[a] message for al-Qaeda, the Islamic State and other terrorists – we are declaring war against you, the terrorists." As such, Anonymous plans to target Jihadist websites and social media accounts linked to supporting Islamic terrorism with the aim of disrupting them and shutting them down
Anonymous hackers take over Victoria's Human Rights Commission website.
“AnonPlus puts offline sites that actively contribute to the control of the masses from the corrupt, that by manipulating information and opinions create false realities: this is censorship!"