Digg is a social news website. Prior to Digg v4, its cornerstone function consisted of letting people vote stories up or down, called digging and burying, respectively. Digg’s popularity prompted the creation of copycat social networking sites with story submission and voting systems. The website traffic ranked 190th, behind one of those competitors, Reddit, by Alexa.com as of December 5, 2011. Quantcast estimates Digg’s monthly U.S. unique visits at 4.3 million.