In musical terminology, it refers to a collection of Gushehs (short, codified melodies) organized into seven Dastgahs (Shur, Mahur, Homayun, Nava, Segah, Chahargah, and Rast-Panjgah) and five Avazes (Bayat-e Tork, Abu-Ata, Dashti, Afshari, and Bayat-e Esfahan). Each Dastgah consists of dozens of Gushehs; the exact number varies by the master’s tradition, but generally, the Radif encompasses over 250 melodic pieces, with a full performance of a single Dastgah potentially lasting up to two hours.
Unlike Western classical music, which relies on harmony, Iranian music emphasizes "melody" and "rhythm" (iqa’). It utilizes "microtones"; while musicology sometimes uses the simplified term "quarter-tone" to describe these intervals, Iranian music actually relies on more subtle, non-standard intervals (such as Sori and Koron), which distinguish it from pure Western systems. The primary instruments of Iranian traditional music include the Tar, Setar, Tombak, Kamancheh, Ney, Santur, Barbat (Oud), and Qanun. Vocals (Avaz) are an inseparable part of Iranian music, and great vocalists (such as Qamar-ol-Moluk Vaziri, Mohammad Reza Shajarian, and Alireza Ghorbani) perform classical Persian poetry (by Hafez, Saadi, Rumi, Ferdowsi, and Attar) based on these Dastgahs and Avazes. The Radif was codified in its current form during the 19th century (Qajar era) by great musicians such as Agha Ali-Akbar Farahani, Mirza Abdollah Farahani (the main editor of the modern Radif), and Darvish Khan. In 2009, it was inscribed on the UNESCO Representative List of the Intangible Cultural Heritage of Humanity on behalf of Iran.
The influence of the Iranian Radif on the music of the ECO region is profound and extensive. The "Maqam" system in Turkey and Azerbaijan, and the "Shashmaqam" in Uzbekistan and Tajikistan, all share common roots with the Iranian Radif. There are significant modal similarities between the Iranian "Dastgah-e Shur" and the "Maqam Shur" in Iraq and Azerbaijan, as well as the "Makam Uşşak" in Turkish music. However, from a musicological standpoint, the performance structure, modal path, and melodic function differ in each system, and they cannot be considered "direct equivalents." In musicology, there is a subtle distinction between "Maqam" (prevalent in Arab and Turkish music, which is based more on foundational melodies) and "Dastgah" (which, in Iranian music, is a more codified system based on an educational Radif).
These similarities are not accidental; they are the result of centuries of cultural exchange via the Silk Road, courtly travels, and the migration of mystics and minstrels between Iran, Anatolia, the Caucasus, and Central Asia. For example, great musicians such as Ali-Asghar Bahari (Kamancheh player) and Mohammad Reza Shajarian have held joint concerts with Azerbaijani and Turkish artists, demonstrating the deep connection between these musical traditions. Furthermore, the Azerbaijani "Tar," which has slight differences from the Iranian Tar (in the number of strings and bowl shape), is directly adapted from it, and there has been mutual historical influence among Persian, Turkish, and Caucasian cultures in the formation of string instrument families in the ECO region (such as the Bağlama in Turkey). In Afghanistan, "Herati" and "Kabuli" classical music are still performed based on these same Iranian Dastgahs (Shur, Mahur, Segah), and singers such as Ustad Mohammad Hussain Sarahang, Ustad Nashanas, Ustad Rahim Bakhsh, and Ustad Qasim have drawn inspiration from the Iranian Radif.
Iranian traditional music (the Radif) is living proof of the "cultural unity of the ECO region in its underlying layers." This musical system, developed and perfected in Iran, has transcended political borders to become the shared heritage of Turkey, Azerbaijan, Central Asia, Afghanistan, and Iraq. The Radif offers immense potential for "arts-based cultural diplomacy." Music teaches us that linguistic and political differences have never been able to sever the emotional and spiritual ties of the nations of this region. Just as the Bağlama in Turkey and the Tar in the Caucasus share deep historical ties with the melodies heard in Tehran, the ECO strives to utilize this common language (which "knows no borders") to resonate a message of peace and convergence from the Persian Gulf to Samarkand. Music is a language that transforms dry, formal diplomacy into a living, audible, and enduring experience in the minds of nations.