Mozilla Thunderbird is an open source email client whose functionalities and features are equal to or better than that its commercial rivals. It is a good alternative to the other commercial email clients in the market and even manages to outperform the competition many times. The software supports both POP and IMAP clients and usenet news reader is integrated with the email client.
The other features of Thunderbird include junk mail filtering and protection from phishing attacks. With a customizable and friendly user interface and advanced features, Thunderbird gives tough competition for the webmail clients and other popular email products.
Thunderbird has the basic features such as multiple identities, junk mail filters, Microsoft exchange server support, HTML support and support for POP and IMAP. The security features worth noting are S/MIME, message encryption, built in phishing detector and digital signing. Though all these features are supported, there is no reduction in performance and speed.
The new features of thunderbird include a back/forward button which allows you to review the messages which you have already read. The tag names help you to get things organized across multiple message folders. Another high point is the ability to save the search results. You can also customize the look and feel of folder panes.