A jali or jaali, (Hindi:जाली jālī, meaning "net") is the term for a perforated stone or latticed screen, usually with an ornamental pattern constructed through the use of calligraphy and geometry. This form of architectural decoration is found in Indian architecture, Indo-Islamic Architecture and Islamic Architecture.
Early jali work was built by carving into stone, generally in geometric patterns, while later the Mughals used very finely carved plant-based designs, as at the Taj Mahal. They also often added pietra dura inlay to the surrounds, using marble and semi-precious stones.
The jali helps in lowering the temperature by compressing the air through the holes. Also when the air passes through these openings, its velocity increases giving profound diffusion. It has been observed that humid areas like Kerala and Konkan have larger holes with overall lower opacity than compared with the dry climate regions of Gujarat and Rajasthan.
With compactness of the residential areas in the modern India, jalis became less frequent for privacy and security matters.
Details of marble Jali screens around royal cenotaphs, Taj Mahal
Jali in Sidi Saiyyed mosque in Ahmedabad
Jali at Tomb of Salim Chishti, Fatehpur Sikri