A tughra (Ottoman Turkish:طغرا‎ tuğrâ) is a calligraphic monogram, seal or signature of a sultan that was affixed to all official documents and correspondence. It was also carved on his seal and stamped on the coins minted during his reign. Very elaborate decorated versions were created for important documents that were also works of art in the tradition of Ottoman illumination, such as the example of Suleiman the Magnificent in the gallery below.