Digital Rights Management (DRM) tools or Technological Protection Measures (TPM) are a set of access control technologies for restricting the use of proprietary hardware and copyrighted works. DRM technologies try to control the use, modification, and distribution of copyrighted works (such as software and multimedia content), as well as systems within devices that enforce these policies.
The use of digital rights management is not universally accepted. Proponents of DRM argue that it is necessary to prevent intellectual property from being copied freely, just as physical locks are needed to prevent personal property from being stolen, that it can help the copyright holder maintain artistic control, and that it can ensure continued revenue streams. Those opposed to DRM contend there is no evidence that DRM helps prevent copyright infringement, arguing instead that it serves only to inconvenience legitimate customers, and that DRM helps big business stifle innovation and competition. Furthermore, works can become permanently inaccessible if the DRM scheme changes or if the service is discontinued. DRM can also restrict users from exercising their legal rights under the copyright law, such as backing up copies of CDs or DVDs (instead of having to buy another copy, if it can still be purchased), lending materials out through a library, accessing works in the public domain or using copyrighted materials for research and education under the fair use doctrine.
Worldwide, many laws have been created which criminalize the circumvention of DRM, communication about such circumvention, and the creation and distribution of tools used for such circumvention. Such laws are part of the United States' Digital Millennium Copyright Act, and the European Union's Information Society Directive, (the French DADVSI is an example of a member state of the European Union ("EU") implementing the directive).