The Electronic Frontier Foundation reports that digital rights management is technology that allows copyright holders to restrict who is able to download, copy, view and share their copyrighted material. It has proliferated due to the Digital Millennium Copyright Act of 1998, which aimed to make attempts to circumvent DRM illegal.
The foundation further reports that when DRM is used by a media publisher users find that they are sometimes limited in activities they can perform with the media. DVD and Blu-ray producers' DRM prevents users from copying movies onto personal computers. Some e-books from Amazon do not work on readers other than Amazon's Kindle, and this is a result of Amazon's DRM. Many applications and video games require DRM authentication each time the program runs. If the publisher's authentication server is down or Internet access is unavailable, it may not be possible to use the software.