In viral marketing, the aim is to spread awareness about a product offering, service or concept using word-of-mouth behaviors. Unlike spam, which is based on a massive distribution of unsolicited emails, viral emails use social networking aspects to ensure their goals of wide propagation. This is one of the strengths of viral email to marketers - while users are quick to delete email from marketers, they are less likely to delete the email if it comes from a person that they know.