Where did the word German come from?

The name Deutschland and the other similar-sounding names above are derived from the Old High German diutisc which originally meant "of the people". This in turn comes from a Germanic word meaning "folk" (leading to Old High German diot, Middle High German diet), and was used to differentiate between the speakers of Germanic languages and those who spoke Celtic or Romance languages. These words come from *teuta, the Proto-Indo-European word for "people" (Lithuanian tauto, Old Irish tuath, Old English þeod).