SpamAssassin uses a unique point system to filter your e-mail. Each message is analyzed and assigned a score based on a list of rules. If the total score of the e-mail is equal to or greater than your Required Hits value, your message will be marked as spam. Depending on your personal preference, you can set this number as high (lenient) or low (strict) as you like, though the default value of five is suitable for most people.