The book categorizes Iranian architecture to 6 main styles. Pre-Islamic architecture is categorized in two styles Parsi and Parti while the post-Islamic architecture is categorized in 4 styles; Khorasani, Razi, Azari and Esfahani.
The Parti style is a style of historical Iranian architecture. This architectural style includes designs from the Seleucid, Parthian, and Sassanid eras, reaching its apex of development in the Sassanid period. Examples of this style are Ghal'eh Dokhtar, the royal compounds at Nysa, Anahita Temple, Khorheh, Hatra, the Ctesiphon vault of Kasra, Bishapur, and the Palace of Ardashir in Ardeshir Khwarreh. The Parti style of architecture appeared after Alexander the Great's conquest of the Achaemenid Empire in the 3rd century BCE, and historically includes the Sassanid, Parthian, and post Islamic eras, up to the 9th–10th centuries. The remains of the architectural style of this period are not abundant, and although much was borrowed and incorporated from Greek designs and methods, architects and builders of this age employed many innovative concepts of their own as well.
Khorasani
The Khorasani style is an architectural style when categorizing Iranian architecture development in history. It is the first style of architecture appearing after the Muslim conquest of Persia, but is highly influenced by pre-Islamic designs. Landmarks of this style appear in the late 7th century, and span through the end of the 10th century CE. Examples of this style are Mosque of Nain, Tarikhaneh-i Damghan, and Jame mosque of Isfahan
The "Azerbaijani style" or "Azeri style" is a style of Iranian architecture developed in Iran's historic Azerbaijan region. Landmarks of this style of architecture span from the late 13th century to the appearance of the Safavid Dynasty in the 16th century CE. Chronologically the Azeri style is the fifth of the six historic styles of Iranian architecture, between the Razi style and the later Isfahani style. Examples of this style are Dome of Soltaniyeh, Arg e Tabriz and Jameh Mosque of Urmia.
Esfahani
The "Esfahani" or "Isfahani style" is a style of architecture when categorizing Iranian architecture development in history. Landmarks of this style span through the Safavid, Afsharid, Zand, and Qajar dynasties starting from the 16th century to the early 20th century. The Isfahani style is the last style of traditional Persian–Iranian architecture.