Google has joined Wikipedia and other sites around the world, including in Canada, to protest anti-piracy legislation being considered in the U.S. Congress.

In a statement, Vancouver-based pro-internet organization OpenMedia.ca, a non-profit organization that promotes an open and affordable internet, said it was joining the protest alongside domain registrar Tucows and microblogging service Identi.

Wikipedia's English-language site shut down at midnight ET Tuesday to protest the Stop Online Piracy Act (SOPA) in the House and the Protect Intellectual Property Act under consideration in the Senate. Both proposed laws are aimed at shutting down sites that share pirated movies and other content.

They are designed to crack down on sales of pirated American products overseas, and they have the support of the film and music industry. Internet companies such as Google, Facebook, Yahoo, Twitter, eBay and AOL, are among the opponents who say the bills would hurt the industry and infringe on free-speech rights.

Not only is OpenMedia.ca temporarily darkening its website in solidarity, it is also providing an online tool that allows Canadians to join their U.S. counterparts, and millions of people worldwide, in speaking out against controversial censorship bills.

In an email to CBC News, the group's executive director said internet users have a lot to lose if SOPA is passed because it could fundamentally reshape the internet in the U.S., Canada, and the rest of the world.

"We at OpenMedia.ca wanted to show our support for the protests against SOPA by going black. We hope that this will send a message to U.S. decision-makers that Canadians, in addition to their own constituents, will not stand for this bill," said Steve Anderson.

"It's important that Canadians are informed, engaged, and able to participate in the policy-making process. Clearly SOPA has deep ramifications for Canada; we wanted to give the pro-internet community here an avenue to express their concerns about this problematic bill."

Toronto-based Tucows, best known for its software downloading service, will shut down access to its site for 12 hours.

"We want them to really understand this type of legislation is not needed and our real goal is to get Americans to call their senators. That's a big part of what we're doing with the blackout," Tucow's vice president of products Ken Shafter told CBC News.

Canadians need to pay close attention to this fight said University of Ottawa law professor Michael Geist.

"Canadians who think they are safe from some of the provisions in SOPA need wait only a couple of years because it seems virtually certain the U.S. will pressure Canada and other countries to adopt similar kinds of measures in the future."

Similar laws are already being proposed here in Canada and Geist said they're troubling because they go far beyond what's necessary to protect Hollywood and the music industry from copyright infringement.

New York-based Appitalism —the first site to combine a social community with an online store to help consumers discuss and download digital content for all devices — joined the online demonstration by going dark starting at midnight sharp Tuesday night.

In an email to CBC News, Appitalism CEO Simon Buckingham said that passing the bills would infringe freedom of expression and severely damage online innovation.

"Because of SOPA, we've spent the day not serving customers but instead sitting on our sofa, because we believe that SOPA and PIPA will likely restrict people's access to online information, not just in the United States but around the world," Buckingham said.

"SOPA and PIPA impacts the way an independent user will use the internet. Passing this law would make it much more difficult for us to enjoy and benefit from the sites that we frequent on a daily basis."

Google.com's home page linked to a petition urging Congress: "Don't censor the Web." Social news website Reddit.com is shutting down for 12 hours on Wednesday, but most companies are staying up.

Dick Costolo, CEO of Twitter, said he opposes the legislation as well, but shutting down the service was out of the question. "Closing a global business in reaction to single-issue national politics is foolish," Costolo tweeted.

The 24-hour Wikipedia blackout is an unprecedented move for the online encyclopedia. However, it's not a total blackout: the block can be bypassed by changing browser settings or by using the version of the site designed for cellphone screens.

"Our purpose here isn't to make it completely impossible for people to read Wikipedia, and it's okay for you to circumvent the blackout. We just want to make sure you see our message," Wikipedia said in a statement.

Instead of encyclopedia articles, visitors to the site saw a stark black-and-white page with the message: "Imagine a world without free knowledge." It carried a link to information about the two congressional bills and details about how to reach lawmakers.

It is the first time the English site has been blacked out. Wikipedia's Italian site came down once briefly to protest an internet censorship bill, which died, put forward by the Berlusconi government.

Blackout attracts support, criticism

A growing body of critics who are speaking out against the legislation, but some of Wikipedia's volunteer editors are so uneasy with the blackout that they have blacked out their own user profile pages or resigned their administrative rights on the site to protest. Some said the blackout is akin to fighting censorship with censorship and jeopardizes Wikipedia's pillars of conduct, which includes writing articles from a neutral point of view.

But Wikipedia founder Jimmy Wales disagreed, tweeting, "The encyclopedia will always be neutral. The community need not be, not when the encyclopedia is threatened."

The Wikimedia Foundation, which administers the site, announced the blackout late Monday after polling its community of volunteer contributors and editors and getting responses from 1,800 of them.

With files from The Associated Press