Wikipedia has announced it will join an Internet 'black out' on Wednesday to protest a controversial anti-piracy bill being considered by the US congress.
Jimmy Wales, co-founder of the crowd-sourced online encyclopaedia, announced on Twitter that the site would join the demonstration.
Wikipedia will 'go dark' at midnight EST on Tuesday until midnight on Wednesday. Only English language versions of the site will be shut down.
"It is the opinion of the English Wikipedia community that both of these bills, if passed, would be devastating to the free and open web," Wikipedia said in a statement.
"The overwhelming majority of participants support community action to encourage greater public action in response to these two bills."
Wales said that the shut-down was a "community" decision, taken after a consensus was reached by "Wikipedians"on the website's community pages.
Wales told his 51,000 Twitter followers that the aim was to send a "message" to Washington. He estimated that around 100m English-speaking people will be affected by the blackout, the idea for which first emerged on Reddit, and suggest that students "do your homework early" before the protest began.
In a press release Wikipedia said:
Over the course of the past 72 hours, over 1800 Wikipedians have joined together to discuss proposed actions that the community might wish to take against SOPA and PIPA. This is by far the largest level of participation in a community discussion ever seen on Wikipedia, which illustrates the level of concern that Wikipedians feel about this proposed legislation. The overwhelming majority of participants support community action to encourage greater public action in response to these two bills. Of the proposals considered by Wikipedians, those that would result in a "blackout" of the English Wikipedia, in concert with similar blackouts on other websites opposed to SOPA and PIPA, received the strongest support.
The Stop Online Piracy Act (SOPA), currently being debated in the US House of Representatives, has proven controversial for transferring responsibility for policing copyright online from law enforcement to websites and internet service providers.
The new law would make it easier for American companies and copyright holders to remove access to foreign websites accused of hosting illegal copies of movies, TV shows and music.
Several other websites including Boing Boing and Reddit said that they will join the blackout.
Media owners including Rupert Murdoch have argued that the law will provide necessary protections to the US creative industries.
Murdoch has been particularly vocal in recent days via Twitter, where he attacked President Obama after it said on Monday that it would not approve the bill in its current form, which in effect means it will have to go back to the drawing board.
Despite the White House withdrawing support for the bill campaigners have not been placated, arguing that SOPA is not yet off the table and adding that another bill, the Protect Intellectual Property Act (PIPA), currently being looked at by the Senate, also poses a threat.
Internet giants including Google and Facebook have led the lobbying effort against the bill, supported by a mass uprising of internet users, arguing that it could cause irrevocable damage to freedom online.
Responding to Murdoch's criticism, a Samantha Smith, a Google spokesperson, said that he had been speaking "nonsense".
The issue is not copyright, Google believes, but censorship.
"Last year we took down 5 million infringing Web pages from our search results and invested more than $60 million in the fight against bad ads," Smith said. "Like many other tech companies, we believe that there are smart, targeted ways to shut down foreign rogue websites without asking US companies to censor the Internet."
Google and Facebook have not said whether they will join the blackout, while Twitter has come out against it.
"That's just silly," said Dick Costollo, Twitter's CEO, via the service:
Users of all three sites have declared they will flood the services with links and information about SOPA throughout the blackout period.