Anti-Spam
Anti-Spam or AS is the common name for service or software which seeks to reduce/remove the receipt of unsolicited or harmful content in email and other messaging clients. Examining the sender, subject, body contents and other heuristics associated with a message is one technique, but AS can also extend to scoring a threat using other technologies such as RBL, URLBL, DMARC, SPF, DKIM amongst others.