Diwani is a calligraphic variety of Arabic script, a cursive style developed during the reign of the early Ottoman Turks (16th century - early 17th century).
It was labeled the Diwani script because it was used in the Ottoman diwan and was one of the secrets of the sultan's palace.
A Diwani text adorned with a tugrah, a complex calligraphic seal, represented the authority of the Sultan and the Ottoman state.
It is still used in the correspondence of kings, princes, presidents, and in ceremonies and greeting cards, and has a high artistic value.
Mural artist and calligrapher Fatma Al Sharshani uses the script in her work, most notably in her mural Never Ending / Endless, which is located in Portland, USA.