|MadSci Network: Computer Science|
E-Mail filter is a blocking feature that some servers or e-mail programs have, it is just a way to tell the program what e-mails you don't want to receive. The most basic blocking engine is one where you specify the email addresses you don't want to receive that way whenever you get one email it will compare against the list and reject or erase the incoming email if it is on the list. This type of program will be on the email server program or on the email client program, other variations will block out emails according to some rule like all the email addresses that start with john for example or all the email addresses that come from @mailserver.com
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