Viral marketing and viral advertising refers to marketing techniques that seek to exploit pre-existing social networks to produce exponential increases in brand awareness, through processes similar to the spread of an epidemic.

The term viral marketing was originally coined to describe various free email services' practice of appending advertising for themselves to outgoing mail from their users. The assumption is that if such an advertisement reaches a "susceptible" user, that user will become "infected" (i.e., sign up for an account) and can then go on to infect other susceptible users. As long as each infected user sends mail to more than one susceptible user on average (i.e., the basic reproductive rate is greater than one), standard results in epidemiology imply that the number of infected users will grow according to a logistic curve, whose initial segment appears exponential.

More generally, viral marketing is sometimes used to describe some sorts of Internet-based stealth marketing campaigns, including the use of web logs, seemingly amateur web sites, and other forms of astroturfing to create word of mouth for a new product or service.

The term "viral advertising" refers to the idea that people will pass on and share cool and entertaining content; this is often sponsored by a brand, which is looking to build awareness of a product or service. These viral commercials often take the form of funny video clips, or interactive Flash games, images, and even text.

Examples of viral marketing

• Burger King's The Subservient Chicken
• Halo's Haunted Apiary
• Ford Motor Company's SportKa advertisements
• Google's Gmail
• Rubbermaid's Tupperware parties
• Sharp's Dagobert Steinitz puzzle

See also

• Memetics (The concept of ideas as self-replicating entities, like genes or viruses)

External Links

Viral Marketing article (http://www.businessweek.com/bwdaily/dnflash/aug2000/nf20000830_601.htm) from Business Week

• archives viral as well as as TV ads, reports on new campaigns (http://ad-rag.com/)
• Buzz and Wireless advertising, SMS, MMS, flash games, films (http://adverblog.com/)
• mainly viral films (http://www.viralmeister.com/)
• Viral Marketing on the Web (http://viral-power.blogspot.com)
• Lycos Viral Chart (http://viral.lycos.co.uk/)