Mozilla Thunderbird is an e-mail application developed by Mozilla Foundation. It is a free, cross-platform e-mail and news application. Nice to Know: Mozilla Suite is a cohesive collection of integrated Thunderbird. A theme can change the toolbar icons or the complete appearance of an application. • Cross-Platform Support. Thunderbird is used on various platforms, such as Ubuntu, Microsoft Windows, Mac OS talk over the Internet for free. The default instant messenger client on Ubuntu is Pidgin, a cross-platform instant messenger that supports var- ious popular IM network protocols. Using Pidgin, you can