A dastgah is a system of musical modes used in traditional Persian music. Each dastgah consists of a collection of notes and specific melodic patterns that guide musicians in improvisation and composition. There are several dastgahs, each with its own unique character and emotional expression. In addition to the main dastgahs, there are also sub-modes called goushehs, which provide further variation and depth. Musicians often perform dastgahs in a free-form style, allowing for personal interpretation while adhering to the established framework. This system is central to the rich heritage of Iranian music.