What’s necessary when you speak and prefer to speak one language, but your neighbor speaks and prefers to speak a different language and neither of you understands the native, preferred language spoken by each other? Lingua Franca!
A lingua franca (Frankish tongue), is a generally accepted term for a third, "bridge language," shared by speakers of completely different languages in order for them to understand each other. A great example of a widely used lingua franca is English, officially and universally used for telephony in civil aviation, where pilots and air traffic controllers are required to speak or understand it as the fail-safe means of communicating with, or receiving instructions from, one another.
For a list of worldwide lingua francas, some surprisingly so, click here.
