First of all, it should be stressed that all Jews have the same Torah.
Jews may be classed according to lifestyle, geography, or outlook.
Lifestyle: there are Jews who are more stringent (Orthodox) or less stringent (Conservative, Reform) in their observance of the Torah's commands.
Geography: there are Ashkenazi (Western) Jews and Sephardi/Mizrahi (Eastern) Jews. Ashkenazim lived in Europe, while Sephardim lived in pre-expulsion Spain and North Africa. (There are others too, such as Yemeni, Romaniote, and Persian Jews, but the above are the largest groups.) All Jews are interrelated and originate in the Middle East, as shown by DNA analyses.
Outlook: among the religious Jewish communities, there are the Yeshiva community, Hassidim, and Modern Orthodox. (Hassidim are the ones who wear long frock-coats.)
The 3 main religious groups are: -Christianity -Judaism (Jewish) -Islamic The previous answer is not correct. The religions listed above are the Abrahamic Religions and not the main religious groups of the world. There are literally hundreds of thousands of religious groups, and possibly thousands of "main" religious groups.
Israel
Jerusalem
Rabbis and cantors
Yes...
Of course not.
The is no such thing as a "judaism".
No, they are not racial groups but religious groups.
The protestants make up 6 different religious groups; or denominations. The 6 different sects of the protestant religious groups are puritans, Methodists, Presbyterians, Baptists, Adventists, Pentecostals.
Judaism does not have a centralized leadership.
Belief in God and in the Torah.
Jews worship in synagogues.