In the past year, politics has dominated a lot of the conversation on social media in the United States. According to Facebook’s 2013 year in review trends, the government shutdown was one of the most talked-about topics on the social platform in the U.S., coming in second after the Superbowl.

Jason Alden/Bloomberg (Jason Alden/Bloomberg)

Other political news making the top 10 most discussed topics in the United States included the Syria crisis (No. 4), George Zimmerman (No. 7) and the presidential inauguration (No. 10). Other topics on the list included the Boston Marathon, Harlem shake and Pope Francis.

Other Web sites' year-end lists of 2013 trends also included many political topics and figures.

According to Bing's tally of the most-searched news stories of 2013, Americans were looking for George Zimmerman trial (the fourth-most searched term on the list), gun rights (No. 5), Syria (No. 7), Anthony Weiner (No. 8) and the fiscal cliff (No. 10).

On Ask.com, the most-searched topics included the following questions: Will the U.S. invade Syria?; Why was George Zimmerman acquitted?; and How far in debt is Detroit?