"In 1994 the National Science Foundation ended its prohibition of commercial speech on the Internet. At that time, e-mail and Usenet were the main forums for communication, and simple publishing systems such as Gopher were trying to establish a wider user base. The Web had barely emerged. That year a law firm named Canter & Siegel posted the first mass commercial spam on Usenet, hiring a Perl programmer to generate advertisements for its "Green card lottery" services, then blasting these to over 6,000 newsgroups. They became celebrities as well as villains, and promptly launched themselves as an outfit producing spam for others, promoting the benefits of spamming, and writing books on "Internet marketing". Since then no online forum has been safe from inappropriate commercial advertising. As the Web has become a more and more important venue for online discussion, and as Web 2.0 techniques have opened up venues for people to write to the Web as much as to read it, the problem of spam has grown with a vengeance.
"Sometimes Web spam is a minor nuisance, but more often it's a pernicious problem. Spammers will often not be content to post one or two messages, but will often flood forums with their messages, until it overwhelms the desired subject matter. Sometimes the spam includes pornographic or antisocial messages that discourage participation. Most search engines will devalue pages with such messages, or with links to sites associated with spam, which means that spam can reduce your search engine optimization. And the final injury is that Web publishers end up wasting resources on spam-fighting, taking time way from other tasks."
