Digital rights management (DRM) is a generic term that refers to access control technologies used by hardware manufacturers, publishers and copyright holders to limit usage of digital media or devices. The term is used to describe any technology which makes the unauthorized use of media or devices technically formidable, and generally doesn't include other forms of copy protection which can be circumvented without modifying the media or device, such as serial numbers or keyfiles. It can also refer to restrictions associated with specific instances of digital works or devices.

Digital rights management has been and is being used by content provider companies such as Sony, Apple Inc., Microsoft and the BBC.

The use of digital rights management is controversial. Advocates argue it is necessary for copyright holders to prevent unauthorized duplication of their work to ensure continued revenue streams. Opponents, such as the Free Software Foundation, maintain that the use of the word "rights" is misleading and suggest that people instead use the term Digital Restrictions Management (DRM). Their position is essentially that copyright holders are attempting to restrict use of copyrighted material in ways not covered by existing laws. The Electronic Frontier Foundation, and other opponents, also consider DRM systems to be anti-competitive practices.

In practice, all widely-used DRM systems have been defeated or circumvented when deployed to enough customers. Restricting copying of audio and visual material is especially difficult due to the existence of the analog hole, and there are even suggestions that effective DRM is logically impossible for this reason.

Introduction

Digital rights management technologies attempt to control use of digital media by preventing access, copying or conversion to other formats by end users. Long before the arrival of digital or even electronic media, copyright holders, content producers, or other financially or artistically interested parties had business and legal objections to copying technologies. Examples include: player piano rolls early in the 20th century, audio tape recording, and video tape recording (e.g. the "Betamax case" in the U.S.). Copying technology thus exemplifies a disruptive technology.

The advent of digital media and analog/digital conversion technologies, especially those that are usable on mass-market general-purpose personal computers, have vastly increased the concerns of copyright-dependent organizations, especially within the music and movie industries. While analog media inevitably loses quality with each copy generation, and in some cases even during normal use, digital media files may be duplicated an unlimited number of times with no degradation in the quality of subsequent copies. The advent of personal computers as household appliances has made it convenient for consumers to convert media (which may or may not be copyrighted) originally in a physical/analog form or a broadcast form into a universal, digital form (this process is called ripping) for location- or timeshifting, combined with the Internet and popular file sharing tools, has made unauthorized distribution of copies of copyrighted digital media (so-called digital piracy) much easier. In effect, copyright-dependent organizations regard every consumer with an Internet connection as a potential node of a distribution network that could be used to distribute unauthorized copies of copyrighted works.