Email is a very powerful, all reaching medium. Get your message right and your friends and customers will do your work for you. They can forward on your message, your brand, your product name - and begin a process that could reach millions around the world.But what, if any, are the rules? It's not easy to get it right when so far there hasn't been much information on what works. Viral marketing is THE marketing buzzword. So what's it all about? How does it work? How did it all start? How effective is it? When is viral marketing appropriate? Who has succeeded? How can we learn from those who have succeeded and those who have failed?These are just some of the questions answered in viral marketing. It also provides an understanding of what it is about people that makes them want to pass on an email to a friend or colleague - and how to ensure they do so for your benefit.