Wordpress, Reddit, Mozilla and Twitpic have also shut down their websites in a move they hope will raise awareness about the Stop Online Piracy Act and its Senate counterpart, Protect Intellectual Property Act (PIPA).
The Motion Picture Association of America (MPAA) claims that the blackout is "irresponsible" and a "stunt," BBC News reported.
However, the websites and internet companies holding blackouts believe that under the rules that SOPA and PIPA introduce, start ups will not be able to handle the costs that come with defending their sites against possible violation, CBS News explained.
"The authors of the legislation don't seem to really understand how the internet works," said Wordpress's co-founder Matt Mullenweg to the BBC.
Former Senator Chris Dodd, chairman and CEO of the MPAA, called the blackout a "gimmick" in a prepared statement.
"It's a dangerous and troubling development when the platforms that serve as gateways to information intentionally skew the facts to incite their users in order to further their corporate interests," Dodd said.
The White House announced over the weekend that it wants to see modifications of the legislation, and authors of both bills have decided to set aside most of the controversial language. A procedural vote is scheduled on Jan. 24 in the Senate.
Meanwhile, many are learning how dependent they are on their beloved internet websites.
Here's a Storify of students responding to Wikipedia's blackout: