Venture capitalists Steve Jurvetson and Tim Draper first coined the term “viral marketing” in the Netscape M-Files newsletter in 1997. The popular version of this article appeared in the November 1998 Business 2.0 article as “Turning Customers into a Sales Force.” At the time, they defined the concept—which was inspired by the pattern of adoption of Hotmail beginning with its launch in 1996—loosely as “network-enhanced word of mouth.”

Viral marketing, along with viral advertising, refer to marketing methods that use existing social networks to exponentially increase product and brand awareness by means of viral processes similar to those involved in the spread of an epidemic. Viral marketing aims to create a persistent infection. The social networks exploited by viral marketing are usually Internet-based, a medium that powerfully amplifies word-of-mouth. The main features of this marketing method are that every customer becomes an involuntary salesperson simply by using the product, thereby making it feasible to reach a large number of people quickly through exponential growth and at very low cost.

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