Yiddish is a hybrid language of mostly German and some Hebrew. It is written in Hebrew but unlike Hebrew, it is pronounced completely phoenetically. Yiddish was spoken since roughly the tenth century in Eastern Europe and is most closely associated with the Jews living in the Pale of Settlement. It was a language of the home and the street, not a particularly scientific language, but very expressive and poetic. Hebrew was spoken and read only for religious purposes. Yiddish literature and theatre is in my opinion unparalleled in its artistic beauty. A couple of Yiddish writers were Isaac Bashevis Singer and Sholem Aleichem. Sholem Aleichem wrote 'Tevie the Milkman', which would later be adapted into a Broadway play 'Fiddler on the Roof'. Yiddish is still spoken by some Chasidic and Haredi communities, but the language was murdered in Europe by the Nazis ym"sh.