Yiddish is a language of Ashkenazic Jews (the Jews people who live in Central and East Europe). It have not relation whith Sephardic culture who includes the Jews from Spain, Portugal, North Africa, Balcans and other countries of South and West Europe.
Yiddish is a hibrid language from medieval-German and Hebrew. It takes a three-quarters of its vocabulary from German and one quarter from Hebrew. Also, It takes borrow words of other languages from the lands where the Askhenazy Jews have lived. The grammatical structure and the written of Yiddish is based on Hebrew characters.
Until half of the 20th century ,18 million Jews spoke Yiddish, and many of them It had their primary language. Yiddish has fallen on hard times, a victim of both assimilation and murder. Today, less than a quarter of a million people in the United States speak Yiddish. But in recent years, Yiddish has experienced a resurgence and is now being taught at many universities.