Common language

A lingua franca (/ˌlɪŋɡwə ˈfræŋkə/), also known as a bridge language, common language, trade language or vehicular language, is a language or dialect systematically (as opposed to occasionally, or casually) used to make communication possible between people who do not share a native language or dialect, particularly when it is a third language that is distinct from both native languages.

Lingua francas have developed around the world throughout human history, sometimes for commercial reasons (so-called "trade languages") 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 originates with one such language, Mediterranean Lingua Franca.

Lingua franca is a term defined functionally, that is "independently of the linguistic history or structure of the language".Pidgins and creoles often function as lingua francas, but many such languages are neither pidgins nor creoles.

Whereas a vernacular language is used as a native language in a community, a lingua franca is used beyond the boundaries of its original community and is used as a second language for communication between groups. For example, English is a vernacular in the United Kingdom but is used as a lingua franca in the Philippines and India. Russian and French serve a similar purpose as industrial/educational lingua francas in many areas.

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