Yiddish is a Germanic language with about three million speakers, mainly Ashkenazic Jews, in the USA, Israel, Russia, Ukraine and many other countries. The name Yiddish is probably an abbreviated version of ייִדיש־טײַטש (yidish-taytsh), which means "Jewish German".
There have been Jews in area that is now Germany since Roman times. A distinct Jewish culture known as Ashkenazi, or Germanic Jewry, appeared by the 10th century. Ashkenaz was the medieval Hebrew name for Germany, though the Ashkenaz area also included parts of northern France and later spread to Eastern Europe.
The every-day language of the Ashkenazic Jews was Middle High German. They also used Hebrew and their German included Hebrew words and phrases. From the 13th century they started to use the Hebrew script to write their language, which linguists refer to as Judeo-German or occasionally Proto-Yiddish. The earliest known fragment of Judeo-German is a rhyming couplet in a Hebrew prayer book dating from 1272 or 1273.
During subsequent centuries, Judeo-German gradually developed into a distinct language, Yiddish, with two main dialects: Western Yiddish, which was widely spoken in Central Europe until the 18th century, and Eastern Yiddish, which was spoken throughout Eastern Europe and Russia/USSR until World War II. As a result of the Holocaust, Jewish communities throughout Europe were destroyed and the use of Yiddish as an every-day language went into sudden decline.
Source: https://www.yivo.org/yiddish-alphabet, with Yiddish script letter names from Michael Peter Füstumum
Yeder mentsh vert geboyrn fray un glaykh in koved un rekht. Yeder vert bashonkn mit farshtand un gevisn; yeder zol zikh firn mit a tsveytn in a gemit fun brudershaft.
All human beings are born free and equal in dignity and rights. They
are endowed with reason and conscience and should act towards one another
in a spirit of brotherhood.
(Article 1 of the Universal Declaration of Human Rights)
Information about the Yiddish language
The Dora Teitelboim Center for Yiddish Culture
Yiddish alphabet with sound files
Online Yiddish dictionaries
The Yiddish Voice - Yiddish radio station
Jewish Language Research Website
Afrikaans, Alsatian, Bavarian, Cimbrian, Danish, Dutch, Elfdalian, English, Faroese, Flemish, German, Gothic, Icelandic, Limburgish, Low German / Low Saxon, Luxembourgish, Mòcheno, Norn, North Frisian, Norwegian, Old English, Old Norse, Pennsylvania German, Ripuarian, Saterland Frisian, Scots, Shetland(ic), Stellingwarfs, Swedish, Swiss German, West Frisian, Yiddish