http://cornelia.siteware.ch/blog/wordpress/2005/11/26/was-bedeutet-deutsch

Mary_Qin, please also look into the answers for the same question posed by tiffeny on January 11.

The Germans refer to their country as Deutschland. The German national song was Deutschland uber Alles The name Deutschland is derived from the Old High German diutisc, or similar variants from Proto-Germanic *Þeudiskaz, 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). The Italian word for the Germans was tedesco or Tedeschi (variants: todesco, tudesco, todisco) comes from the same Old High German root, although not the name for "Germany" (Germania). The British soldiers fighting in Italy in WW2 shortened this to Teds. Reference Link: http://en.wikipedia.org/wiki/Names_for_Germany