SpamAssassin(tm) is a mail filter to identify spam. Using its rule base, it uses a wide range of heuristic tests on mail headers and body text to identify “spam”, also known as unsolicited commercial email.
SpamAssassin is an open source program located at http://www.spamassassin.org/
You can enable SpamAssassin through your cPanel control panel. We suggest using SpamAssassin with IMAP instead of POP email so you can create a SPAM Folder that can be checked for legitimate email. Although rare, sometimes legetimate email can get marked as Spam. We find spamassassin is HIGHLY effective and use it on our own email servers.
Watch the following video if you want to know more about SpamAssassin.