| DRM stands for Digital Rights Management, or as | | | | offers similar quality to that of AAC and better than |
| some people call it, Digital Restrictions Management. | | | | that of MP3 files. This means that much smaller files |
| Put simply, DRM consists of various restrictions | | | | can have CD quality. WMA is based on the ADvanced |
| applied in music or video files, so their use (such as | | | | System Format (ASF) which can integrate different |
| playback) can be controlled by a third party, usually | | | | streams of audio and video as long as they belong to |
| the company holding the copyright for a song or | | | | the Windows Media family. |
| movie. DRM is not just a copyright protection | | | | RealNetworks & Sony: Both of these companies |
| technique but a whole set of technologies that aim | | | | offer music download services. Real mostly uses the |
| to implement the DRM strategy each distributor of | | | | AAC format with the Helix DRM system, while Sony |
| digital content specifies. As an example, DRM can | | | | uses the OpenMG DRM system on ATRAC3 files. It |
| verify that the user that bought an audio file is | | | | is expected that Sony will support other music |
| actually the same user playing the file. DRM | | | | formats in the future. |
| technology can also be used to limit the number of | | | | Limitations of iTunes and iPod |
| PCs a file can be played on. The major disadvantage | | | | Finally, here are certain things that you should know |
| of DRM is that these restrictions are not always clear | | | | about iTunes DRM: |
| when a user buys a digital product. | | | | 1. Music you buy from iTunes can only be played on |
| Which Multimedia Formats Support DRM? | | | | an iPod. |
| If you're expecting to see MP3 in this list, guess | | | | 2. Files from iTunes can be played on an unlimited |
| again. Due to it's open nature, the MP3 standard is | | | | number of iPods. |
| unable to support DRM. Furthermore, there is no | | | | 3. iTunes allows you to download each song you buy |
| centralized coordination in the development and | | | | only once and of course, you're not allowed to re-sell |
| evolution of the MP3 format so don't expect digital | | | | that song. |
| music stores to offer songs in the MP3 format. | | | | 4. An iPod can also store and play non-DRM music |
| Advanced Audio Coding: The AAC format, used by | | | | files. |
| iTunes and iPod, is based on Apple's QuickTime. It | | | | 5. Any certified .m4p files can only be copied/played |
| was originally designed as a replacement of the MP3, | | | | on 5 authorized computers. |
| and can actually compress files better than the MP3 | | | | 6. Music you buy from iTunes can be copied to a CD |
| format can. | | | | without any DRM limitations. |
| Windows Media Audio: WMA is a closed-source | | | | 7. A playlist consisting of songs you bought from |
| standard of digital music. It was designed to compete | | | | iTunes can only be turned into a CD 7 times (you can |
| with the MP3 but in reality, it's actually AAC's main | | | | make 7 CD copies of the list). |
| competitor, especially with regards to DRM support | | | | 8. You are not allowed to convert a song to a |
| and buying music online. The latest version of WMA | | | | different music format. |