Spam filter: Dispose of advertising waste

Almost everyone has experienced Internet offers for Viagra, unheard-of chances of winning, almost free health insurance or even penis extensions, most of which arrive uninvited in the mailbox. A spam filter is a program or module that filters such unwanted and annoying advertising from the data stream. There are various methods of considerably thinning out such 'spam'.

The blacklist method scans, for example, the sending servers, the email addresses or the headlines for unwanted terms and sets up such a defense regime itself. The Bayesian filter first requires the cooperation of the user, who sorts the first 1,000 or so emails themselves according to 'wanted' or 'garbage'. After that, the filter achieves a hit rate of almost 95 percent. Newer methods target linked URLs (Internet addresses) in the spam mails, and thus the 'traders' of this model, in order to operate consistent waste disposal in virtual space.