Definition - What does Spamming mean?
Spamming is the use of electronic messaging systems like e-mails and other digital delivery systems and broadcast media to send unwanted bulk messages indiscriminately. The term spamming is also applied to other media like in internet forums, instant messaging, and mobile text messaging, social networking spam, junk fax transmissions, television advertising and sharing network spam.
Techopedia explains Spamming
Spamming (especially e-mail spam) is very common because of the economics. Spam advertisers have little to no operating costs and so need only a minute response rate to make a profit. Most spam are commercial advertising, but some contain viruses, adware, or scams.