Iranian/Persian traditional music (also known as mūsīqī-e sonnatī-e īrānī or mūsīqī-e aṣīl-e īrānī) is now modernly classified into the Dastgāh system.
Each of these seven modes, referred to as Dastgāh, are then classified into smaller units (usually only one), each called an āvāz.
Every āvāz consists of short pieces and melodies of music called the gousheh that, although each has its own characteristics, share one central characteristic in the āvāz.
The seven main Dastgāh of Iranian music are modernly known as Shour, Māhour, Homāyoun, Segāh, Chāhārgāh, Rāstpanjgāh, and Navā.
The classification is as below: A complete book in Iranian traditional music is called the radif, which consists of all seven Dastgāh.