SpamAssassin passes a message through a series of rule-based content tests. When a message passes a given test, SpamAssassin assigns a score to it. When SpamAssassin is done with the message, the message has an accumulated score associated with it. You as a system administrator (or, possibily even your users) then determine what the minimum score a message must have in order to be classified as SPAM.
SpamAssassin can integrate nicely with other filters. In fact, it can use other SPAM filters as a part of its rulebase to integrate many various SPAM scanners into one unified SPAM filtration system.
/etc/mail/spamassassin/local.cf is the main configuration file (this is where it is installed by default, but it may be in a different location depending upon how your distribution set it up). This
