calibre is a cool and easy to use e-book manager. It’ll allow you to do nearly everything and it takes things a step beyond normal e-book software. It’s also completely free and open source and great for both casual users and computer experts. calibre’s user interface is designed to be as simple as possible. Large buttons in the main window take care of most of your needs. The vast number of calibre’s features and options is always clearly displayed under intuitive tabs. Its context menus are neatly sorted, so the things you’re looking for almost find themselves on their own. You’re never more than three clicks away from your goal.