A Jew is a person who is of Jewish heritage or who has converted to the Jewish religion. Jews typically consider themselves as a people and not only as adherents of a religion, therefore a Jew is not only one that practices the religion of Judaism, but it is also one who is of Jewish ethnic heritage. According to traditional Jewish law, called Halakha, someone is Jewish if their mother was a Jew or if they have converted to Judaism. Judaism has been described as a religion, a race, an ethnic group, a culture, a nation, and an extended family.
Israel is the only modern country with a Jewish majority, but there are Jewish minorities in many places in the world. Most of them live in large cities in the United States, Argentina, Europe and Australia. Both Israel and the U.S. have over five million Jews. In the Soviet Union there were more than two million Jews, but many of them moved to Israel, the U.S. and other Western countries since the collapse of the Soviet Union.
All ethnic (non-convert) Jews have genetic heritage from the Levant (the region now known as Israel and/or Palestine). Within all of the world's Jews, there are Jewish ethnic groups. The two biggest are called Ashkenazi (who have historically lived in Central and Eastern Europe) and Sephardic (who have historically lived in lands around the Mediterranean Sea, particularly Spain and Portugal). Jews from Arab and Muslim countries are called Mizrahi Jews. There are also Ethiopian Jews, Indian Jews (Bene Israel) and Chinese Jews (Kaifeng Jews). Many of these groups have moved from one place to another. For example, many Ashkenazi Jews live in the United States, and many Sephardic and Mizrahi Jews live in France.
Jews speak the languages of the countries where they live. Hebrew is the language of Judaism because it is the language in which the Bible was written. It is still used for prayers. In Israel, Ivrit, which is the name for the new Hebrew language, is the common language. There are also other Jewish languages such as Yiddish and Ladino which are still spoken and written by some Jews.