Bayesian spam filtering
It is a statistical technique of e-mail filtering.Bayesian spam filtering has become a popular mechanism to distinguish illegitimate spam email from legitimate email (sometimes called "ham"). Many modern mail clients implement Bayesian spam filtering. Users can also install separate email filtering programs.
Like in any other spam filtering technique, email marked as spam can then be automatically moved to a "Junk" email folder, or even deleted outright
Bayesian email filters take advantage of Bayes' theorem. Bayes' theorem is used several times in the context of spam:
a first time, to compute the probability that the message is spam, knowing that a given word appears in this message;
a second time, to compute the probability that the message is spam, taking into consideration all of its words (or a relevant subset of them);
sometimes a third time, to deal with rare words.
