English is a West Germanic language that originated in Anglo-Saxon England. As a result of the military, economic, scientific, political and cultural influence of the British Empire during the 18th, 19th and 20th centuries and of the United States since the late 19th century, it has become the lingua franca in many parts of the world. It is used extensively as a second language and as an official language in Commonwealth countries and many international organizations.

Historically, English originated from several dialects, now called Old English, which were brought to Great Britain by Anglo-Saxon settlers beginning in the 5th century. The language was heavily influenced by the Old Norse language of Viking invaders. After the Norman conquest, Old English developed into Middle English, borrowing heavily from the Norman (Anglo-French) vocabulary and spelling conventions. Modern English developed from there and continues to adopt foreign words from a variety of languages, as well as coining new words. A significant number of English words, especially technical words, have been constructed based on roots from Latin and ancient Greek.