A mail transport agent (MTA) provides the "plumbing" for your email system by taking mail from a client application such as Evolution or Mozilla Thunderbird and routing it to the correct location on the right machine. There are plenty of good MTAs, such as Postfix, Sendmail, and qmail, but these popular mail servers require a large amount of configuration, and may be overkill for users who merely want to set up an MTA to test a Web development project or need to move mail around locally. Smail is a better alternative for these scenarios because it generally requires no configuration, and its memory footprint is less than the more fully featured MTAs.



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