As I mentioned a few times in previous blogs, viral marketing means that information spreads around the internet like a virus. The best known forms of viral marketing are video funnies that we all receive in our e-mail and then send them onto our friends.
It is in our nature that we like giving things to our friends. We also like to tell them interesting information. And that is the principle of viral marketing. When we get something interesting, informative or funny, we send it on to our friends and acquaintances.
You can read about viral marketing in the following free books: 5+ Awesome FREE eBooks Regarding Viral Marketing.
I also warmly recommend the book: World Wide Rave.