Social is the interaction of people, normally in an informal way; media is the various means of storing and transmitting communication, typically about news or products and typically to multiple recipients. Social media blends and blurs these two elements in infinite combinations.

Social media pioneer Robert Scoble once said, “When I say ‘social media’ or ‘new media,’ I’m talking about Internet media that has the ability to interact with it in some way.”

Some of the most prominent examples: Facebook, Twitter, Flickr, YouTube, Wikipedia, blogs and online forums. As of November 2009, Facebook boasted 300 million active users, with 65 million accessing through mobile devices. Twitter had 20 million tweets a day compared with three million a day in March 2008. And Wikipedia had more than 67 million users, with 85,000 active contributors.