====== Spam Filters ====== Spam filtering programs often use a combination of different types of spam filters. The three most common types are basic, challenge/response, and statistical. * Basic filters use a list of terms associated with know spam email messages. * Challenge/response filters send every message back to the sender who must verify that the sent message is not spam. * Statistical filters create and maintain a statistical profile of know spam messages. To learn more about how each of these filters work, click the link below and view the animation. [[animations:spam|Spam filter animation]]