Art Music - also called Classical, Court, Serious, or Formal Music, has advanced structural and theoretical considerations and a written musical tradition
Progressive Art Music -
Children - Music and spoken works by and/ or for youth
Classic Popular Music - Popular Music forms predating rock-and-roll
Experimental - Forms
Jazz - In addition to pure jazz forms, some classic popular forms are here, such as big band swing
Popular Music -
Traditional Music -
Spoken - Includes everything from drama and poetry to instruction and talk shows
Regardless of the date of the recording, it falls under the form which is its closest fit. For example, a rockabilly band performing today is following an early rock form, and would be filed under Popular Music: Early Rock.
The Traditional Music recordings are organized using a method called the United Nations Geoscheme. It was developed by the United Nations Statistics Division. The system organizes the world into macro-geographical regions and subregions following continent geography as much as possible.