An Internet radio device, also called network music player is a hardware device that is capable of receiving and playing streamed media from either Internet radio stations or a home network.
It has expanded enormously with an estimated 19,000 stations currently available, including many traditional FM /AM simulcasting their content over the Internet.
Online music services usually offer millions of songs and thousands of artists for users to choose from.
Station directory services keep a current list of active Internet radio stations, their URI and streaming formats and list them sorted by genre, location, language and other criteria.
Many devices use either proprietary vendor-specific station list servers or dedicated directory services.