Lattice-work or Jaali is a technique used to make perforated stone screen, as decorative element in the architecture. You'll see it generously used in the Fatehpur Sikri's architecture.
A splendid specimen is the one surrounding the Salim Chisti's Tomb.
Complex patterns are carved out of thin sheets of red sand stone, the main material used in the Fatehpur Sikri's construction. These perforated slabs are then installed as windows.