In the past few years, Social Media and Social Media marketing have become buzz words. This is due to the popularity of sites like MySpace, Digg, etc. The social media have two components - user generated contents and the ability to form networks of friends for sharing contents.

In sites like MySpace and Facebook users create their profile pages and use texts, pictures, and videos to embellish the pages. They can then share those contents with others in their friends' network, or the social network

In sites like Digg, YouTube, Flickr users submit summary of news articles, pictures, videos and they vote on the contents submitted by others. Popular contents are featured on the homepage and it drives massive amount of traffic.

There are many variations of the two models described above, including a combination of the two.