List of lingua francas
Turkish is still in use and widely spoken in several areas formerly part of the Ottoman Empire and may be understood by older people in other parts of the Middle East.
Lingua franca
Lingua francas have developed around the world throughout human history, sometimes for commercial reasons (so-called "trade languages" facilitated trade) but also for cultural, religious, diplomatic and administrative convenience, and as a means of exchanging information between scientists and other scholars of different nationalities. The term is taken from the medieval Mediterranean Lingua Franca, a Romance-based pidgin language used by European merchants and sailors during the 2nd millennium. A world language – a language spoken internationally and learned and spoken by a large number of people – is a language that may function as a global lingua franca.