Apple has won a patent on the original concept and interface for the iTunes Store, Patently Apple notes. "Broadly speaking, the invention relates a graphical user interface suitable for reviewing, browsing, previewing and/or purchasing media items. The graphical user interface can be presented to a user at a client (client machine). In one embodiment, the graphical user interface is presented to the user by an application program that runs on the client," part of the patent reads.

"The graphical user interface is also suitable for previewing or purchasing media items in an on-line manner. The graphical user interface can be presented to a user at a client (client machine). In one embodiment, the graphical user interface is presented to the user by an application program that runs on the client."

Apple emphasizes its decision to go with a client-server system, which not only restricts "unauthorized access" to media, but also serves to "limit usage rights to the media by authorized users. The security restricts access to media within media files during downloads as well as while stored at a server and/or client. The graphical user interface can assist users in locating media to be purchased. The media can, for example, be audio, video, or image data," Apple writes.

Some background in the patent suggests that Apple may have considered peer-to-peer or streaming options, but ultimately dismissed them. "Streaming does not store the music files on the subscriber's machine, and thus is less of a concern for the music industry," the patent comments. "However, such a system requires a network connection and network availability in order for subscribers to play songs."

Apple originally filed for the patent in 2004. The iTunes Store itself actually dates back to 2003, and was very limited compared with its modern counterpart. Initially sales were limited to music, and the files were locked down with DRM, making it difficult or impossible to use them on non-Apple devices. Apple eventually lifted that restriction, and the store gradually expanded to include movies, TV shows, mobile apps, and books.

via ipodnn