Main article: History of Mozilla Thunderbird
Originally launched as Minotaur shortly after Phoenix (the original name for Mozilla Firefox), the project failed to gain momentum. With the success of the latter, however, demand increased for a mail client to go with it, and the work on Minotaur was revived under the new name, and migrated to the new toolkit developed by the Firefox team.
Significant work on Thunderbird restarted with the announcement that from version 1.5 onwards, the main Mozilla suite would be designed around separate applications using this new toolkit. This contrasts with the previous all-in-one approach, and will hopefully lead to more efficient and maintainable code, as well as allowing users to mix and match the Mozilla applications with alternatives. The original Mozilla Suite continues to be developed as SeaMonkey.
On December 23, 2004, the Project Lightning was announced for tightly integrating calendar functionality (scheduling, tasks, etc.) into Thunderbird, and is now available as an extension.
On October 11, 2006, Qualcomm and the Mozilla Foundation announced that "future versions of Eudora will be based upon the same technology platform as the open source Mozilla Thunderbird email program." The project is code-named Penelope. An unofficial Eudora/Penelope forum is accessible via web or newsreader.
On July 26, 2007, the Mozilla Foundation announced that Thunderbird would be developed by an independent organization, because the Mozilla Corporation (a subsidiary of the foundation) is focusing on Mozilla Firefox development.[1]
On September 17, 2007, the Mozilla Foundation announced the funding of a new internet communications initiative with Dr. David Ascher of ActiveState. The purpose of this initiative is "to develop Internet communications software based on the Thunderbird product, code and brand".
On February 19, 2008 Mozilla Messaging started operations as a subsidiary of the Mozilla Foundation responsible for the development of email and similar communications. Its initial focus is the upcoming version of Thunderbird 3.
[edit] Features
Thunderbird aims to be a simple e-mail, newsgroup and news feed client. The vanilla version is not a personal information manager, although, with the Mozilla Lightning extension, a big part of a PIM functionality is added. Additional features, if needed, are often available via other extensions.
[edit] Message management
Thunderbird can manage multiple e-mail, newsgroup and RSS accounts and supports multiple identities within accounts. Features like quick search, saved search folders ("virtual folders"), advanced message filtering, message grouping, and labels can help manage and find messages. On Linux-based systems, system mail (movemail) accounts are supported.
[edit] 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[2]
[edit] Extensions
Extensions allow the addition of features through the installation of XPInstall modules (known as "XPI" or "zippy" installation). One example is Lightning, the calendar extension mentioned above.
Extensions and themes (below) available on the Mozilla Update site may be upgraded through the client.
[edit] Themes
Thunderbird supports a variety of themes for changing its overall look and feel. These packages of CSS and image files can be downloaded from Mozilla Add-ons.
[edit] Standards support
Thunderbird supports POP and IMAP. It also supports LDAP address completion. The built-in RSS/Atom reader can also be used as a simple news aggregator. Thunderbird supports the S/MIME standard and extensions like Enigmail add support for the OpenPGP standard.