What is SOPA? Web braces for Stop Internet Piracy Act protest

(AP/ABC7) - Don't be surprised if you can't find Wikipedia today.

The online encyclopedia's English language website is down until midnight. The 24-hour blackout is to protest anti-piracy legislation under consideration in Congress.

The Stop Online Piracy Act and the Protect Intellectual Property Act are designed to crack down on sales of pirated U.S. products overseas.

MORE: Read the full text of H.R. 3261: The Stop Online Piracy Act

Supporters including the film and music industry say the legislation is needed to protect intellectual property and jobs.

Those supporters of the bill include entertainment giants such as Disney, HarperCollins, Major League Baseball, the National Football League the Motion Picture Association of America and Sony. SOPA's sponsor in Congress is Rep. Lamar Smith (R-Texas).

PHOTOS: Which sites are blacked out in protest today?

"The bill ensures that profits from America’s innovations go to American innovators," Smith says in a statement on his website.

Critics say it could hurt the technology industry and infringe on free-speech rights. Tech companies such as Google, Facebook, Yahoo, Twitter, eBay, AOL and others have said it threatens the industry's livelihood.

Several online communities such as Reddit, Boing Boing and others have announced plans to go dark in protest as well.

But Wikipedia volunteer editors who disagree with the shutdown say it threatens the credibility of their work. Editor Robert Lawton says, "Before we know it, we're blacked out because we want to save the whales."