What is SpamAssassin?

Wiki MarkupSpam{{`Assassin is a mail filter to identify spam. It is an intelligent email filter which uses a diverse range of tests to identify unsolicited bulk email, more commonly known as \["Spam"\], also known as unsolicited commercial email (UCE) These tests are applied to email headers and content to classify email using advanced statistical methods. In addition, Spam. These tests are applied to email headers and content to classify email using advanced statistical methods. In addition, Spam}}`Assassin has a modular architecture that allows other technologies to be quickly wielded against spam and is designed for easy integration into virtually any email system.

Want to learn more?

• Questions about using SpamAssassin can be asked on the SpamAssassin-Users MailingLists. However, please note AskingAboutIntegrations.
• BooksAboutSpamAssassin: Published books that discuss SpamAssassin.

Advantages

Spam{{`Assassin's practical multi-technique approach, modularity, and extensibility continue to give it an advantage over other anti-spam systems. Due to these advantages, Spam}}Assassin is widely used in all aspects of email management. You can readily find SpamAssassin in use in both email clients and servers, on many different operating systems, filtering incoming as well as outgoing email, and implementing a very broad range of policy actions. These installations include service providers, businesses, not-for-profit and educational organizations, and end-user systems. Spam`Assassin also forms the basis for numerous commercial anti-spam products available on the market today.

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• Header tests
• Body phrase tests. For more information, see SpamAssassinRules.
• Bayesian filtering (BayesFaq)
• Automatic address whitelist/blacklist (AutoWhitelist)
• Automatic sender reputation system (TxRep)
• Manual address whitelist/blacklist (ManualWhitelist)
• Collaborative spam identification databases (DCC, Pyzor, Razor2); See NetworkTests UsingNetworkTests.
• RBL (DNS Blocklists, also known as "RBLs" or "Realtime Blackhole Lists)DNS Blocklists". See DnsBlocklists
• Character sets and locales

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Even though any one of these tests might, by themselves, mis-identify a \["Ham"\] or \["Spam"\], their combined score is terribly difficult to fool.

About the Apache Software Foundation

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