What are DRMs and when can they be used?

Digital Rights Management Systems - DRMs - are a term commonly used to describe a wide range of technical measures that are licensed for controlling, measuring and enabling use of copyright protected digital content.

Such systems cover a range of technologies with different purposes such as:

• systems to identify owners rights and give information on licensing , e.g. to enable collecting societies to accurately pay royalties - Rights management Information (RMI)
• copy protection systems to prevent unauthorised coping, e.g. may prevent consumers from transferring films stored on DVD to a computer hard drive - Technical Protection Measures (TPM)