Calibre eBook Management is an open source eBook library management on Linux, Macintosh, and Windows platforms that provides library management, conversion of eBooks, synchronization of eBook reader devices, and downloading of messages from the web and converting them to eBook form, as well as a comprehensive eBook reader to help users access collections online. Site FAQs include upgrade support, video tutorials, manuals, general information, tips, inquiries, development information, and forums.