Spam is bombarding the Internet with so many copies of the same message or sending the same message again and again or posting a content on social media again and again and try to force the message on people who would not otherwise choose to or are willing to receive it. Most spam is commercial advertising, often for untrustworthy products, how to earn Trillions of money overnight without spending a penny, quick money earning schemes, or suspicious legal services. Spam costs the sender a very little amount to send, most of the costs are paid by the recipient or the carriers . To the recipient, spam is easily identifiable. If you hired someone to read your mail and discard the spam, they would have little trouble doing it. How much do we have to do, short of algorithms, to automate this process? I think we will be able to solve the problem with fairly simple algorithms.
One specifically unpleasant type of email spam is sending spam to mailing lists (public or private email discussion forums). Because many mailing lists restrict activity to their subscribers, spammers will use programmed tools to subscribe to as many mailing lists as possible, so that they can get the lists of addresses, and use the mailing list as a direct earmark for their attacks.
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