Redditors have sounded the call to arms.

In a blog post on Tuesday, community news-sharing site Reddit announced that it will be shutting down normal operations on January 18 in protest of proposed legislation Stop Online Piracy Act (SOPA) and PROTECT IP Act (PIPA).

"The freedom, innovation, and economic opportunity that the Internet enables is in jeopardy," Reddit admins wrote in the blog post. "Congress is considering legislation that will dramatically change your Internet experience and put an end to reddit and many other sites you use everyday."

If passed, SOPA would allow the U.S. Department of Justice and copyright holders to seek court orders against foreign and even domestic websites that enable or facilitate copyright infringement. If a website is accused, it could be punished by being removed from search engine results, barred from online advertising networks, and blocked from payment processing networks. In other words, sites like Facebook, Wikipedia, YouTube and Reddit could be crippled for hosting or linking to user-uploaded content that potentially infringes on copyrights.

The bill would also make the unauthorized streaming of copyrighted content, such as a song or TV show, a crime punishable by up to five years in prison.

Reddit's 12-hour blackout, which is planned for 8 a.m. to 8 p.m. EST on Wednesday January 18, coincides with a congressional hearing on SOPA, at which tech and security leaders, including Reddit founder Alexis Ohanian, will air their grievances toward SOPA and PIPA.

During the downtime, Reddit will show a live-stream of the hearing and will display a simple statement on why this proposed legislation would mean the end of user-generated content sites.

On Twitter, reactions to the Reddit blackout have been overwhelmingly positive. The hacker group Anonymous came out in support of Reddit, tweeting a link to the blog post announcing the blackout.

In December, Wikipedia co-founder Jimmy Wales considered a site-wide "blank out" to demonstrate what the site might look like should this legislation pass. The blackout never happened, but Wales would go on to withdraw Wikipedia and Wikia domains from GoDaddy as part of the December boycott.

Some suggest that the Reddit blackout could lead to more collective efforts against SOPA. According to VentureBeat, "there have been rumblings that Google, Twitter and Facebook are also planning a collective protest effort against SOPA and PIPA."