An Adobe EPUB eBook is a digital version of a print book that has been optimized for on-screen reading. The text in an EPUB eBook is reflowable, which means that you can change the font, resize the text, or alter the size of your display, and the text will rewrap itself to fit the available viewing area. Adobe EPUB eBooks also support embedded content, allowing, for instance, a Flash video to be embedded within an eBook. Adobe Digital Editions must be installed and activated to download and read EPUB eBooks on your computer. If you want to download and read EPUBs on a mobile device, you must install the OverDrive Media Console app and authorize your device with a free Adobe ID.