If you've ever read an article from The Onion that someone posted to Facebook and mistaken it for real news, you're not alone. Facebook recognizes the issue and is testing out a feature that marks fake news stories with "satire" in its News Feed.
A Facebook representative told Mashable, "We are running a small test which shows the text '[Satire]' in front of links to satirical articles in the related articles unit in News Feed. This is because we received feedback that people wanted a clearer way to distinguish satirical articles from others in these units." The tag is considered especially useful for sites that aren't as well-known as The Onion.
Recently The Daily Currant posted a satirical article about former Alaska Governor Sarah Palin joining Qatar-based Al Jazeera as a commentator, and the Washington Post published it on its website as real news. They paper later posted a correction, but it just shows how satirical articles really can cause confusion.