Probably the most widely known form of spam, it all began here with email spam. Usually involves sending thousands of emails to email address from a list using a spamming tool. Sometimes the emails are a list of real addresses bought or stolen from someone, or are generated on the fly based on a list of potential target domains.

Spam usually tries to sell you porn, drugs or anything else. Sometimes this is a method for sending out spyware, viruses and trojans. Quiet often spammers setup 'botnets' of compromised machines to send out spam. Email addresses are often harvested from webpages, forums, chat rooms, compromised machines and usenet.