Mozilla Thunderbird is a free, open source e-mail and news client developed by the Mozilla Foundation. Thunderbird can manage multiple e-mail, newsgroup and RSS accounts and supports multiple identities within accounts.
Thunderbird gives you IMAP/POP support, a built-in RSS reader, support for HTML mail, powerful quick search, saved search folders, advanced message filtering, message grouping, labels, return receipts, smart address book LDAP address completion, import tools, and the ability to manage multiple e-mail and newsgroup accounts.
- Message management. Thunderbird can manage multiple e-mail, newsgroup and RSS accounts and supports multiple identities within accounts.
- Junk filtering. Thunderbird incorporates a Bayesian spam filter, a whitelist based on the included address book, and can also understand classifications by server-based filters such as SpamAssassin.
- Extensions. Extensions allow the addition of features through the installation of XPInstall modules.
- Themes. Thunderbird supports a variety of themes for changing its overall look and feel.
- Standards support. Thunderbird supports POP and IMAP. It also supports LDAP address completion.
- Internationalization and localization. With contributors all over the world, the client is translated into at least 36 languages/locales, covering a wide number of languages.
- Security. Thunderbird provides enterprise and government-grade security features such as SSL/TLS connections to IMAP and SMTP servers.