What makes things on the Internet go viral?

Japanese youth invade a Tokyo bathhouse to do their version of the YouTube dance craze, the Harlem Shake. What makes some videos go viral? See more YouTube Pictures.

LOLcats. For the uninitiated – those who have somehow been able to avoid what appears to be a nonstop, social media-fueled avalanche of photos of cats doing funny things accompanied by cryptic, grammatically deficient messages – LOLcat is an Internet thing. A big one. It started in 2006 with an image of a fat cat looking at a camera, with the headline "I CAN HAS CHEEZBURGER?" emblazoned across the top. Today, a family of Web sites dedicated to this and other Internet memes sees more than 20 million unique visitors each month [sources: Grossman, cheezburger.com].

That's what Web folks call viral content: Something that spreads so fast on the Internet that it dominates Facebook and Twitter news feeds and racks up page views and clicks the way Elvis Presley used to take down fried peanut butter and banana sandwiches. Often, it's a silly or ridiculous photo or video along the lines of the "cheezburger" cat, a weird Chinese goat or various groups of people doing the Harlem Shake. Sometimes, however, more meaningful pieces like the Kony2012 video depicting the hunt for African warlord Joseph Kony catch Internet fire. Dubbed the fastest growing viral video of all time, the clip garnered 100 million views in just six days [sources: Breakthrough Content, Invisible Children].

Of course, the Internet is chock full o' crazy pet pics, cute babies, strange dance crazes and socially responsible documentaries. Why do some of them get millions of views while others get a few hundred (or less)? It was all the way back in 350 B.C.E. when Aristotle came up with his theory for making speeches memorable. The Greek philosopher concluded that the talk must have an ethical, logical or emotional appeal. These days, it seems tugging on the heart strings is the way to go viral on the Web [source: Konnikova].