DRM (digital rights management) is technology designed to limit copying, sharing and printing of digital media.
Some digital books you borrow from the library are DRM-protected. When you install and activate Adobe Digital Editions, you'll be asked to create an Adobe ID. Creating an ID allows you to borrow a title and use it on more than one computer, or transfer it from your computer to a mobile device. Authorizing more than one computer or mobile device with the same Adobe ID allows you to share the same downloaded file between them.