Editing Anti-spam techniques (section)

===Statistical content filtering===
{{Main|Bayesian spam filtering}}

Statistical, or Bayesian, filtering once set up requires no administrative maintenance per se: instead, users mark messages as ''spam'' or ''nonspam'' and the filtering software learns from these judgements. Thus, it is matched to the ''end user's'' needs, and as long as users consistently mark/tag the emails, can respond quickly to changes in spam content. Statistical filters typically also look at message headers, considering not just the content but also peculiarities of the transport mechanism of the email.

Software programs that implement statistical filtering include [[Bogofilter]], [[DSPAM]], [[SpamBayes]], [[Anti-Spam SMTP Proxy|ASSP]], [[CRM114 (program)|CRM114]], the email programs [[Mozilla]] and [[Mozilla Thunderbird]], [[Mailwasher]], and later revisions of [[SpamAssassin]].