"I can still understand Jewish, but I have difficulty speaking it," a friend of mine told me recently, recalling the language of his Polish-born parents. At the risk of nit-picking, I corrected him by explaining that his parents spoke Yiddish, not "Jewish," and that Yiddish was just one of about half-dozen different "Jewish languages."

Yiddish was the language only of Ashkenazi Jews--people who inhabited central and eastern Europe. (Ashkenaz is the ancient Hebrew word for the German-speaking territories from which their ancestors migrated eastward.) Until the early 1900s, it was the world's most commonly used Jewish language, largely because the Ashkenazim outnumbered the world's other Jewish communities until the Nazi Holocaust.

Since the establishment of Israel in 1948, Hebrew has replaced it as the world's leading Jewish tongue. Yiddish and the other Jewish languages are becoming as obsolete as Latin. Yiddish is still the primary language only of Hasidim and other insular ultra-Orthodox Jewish sects who regard Hebrew as too sacred for common usage.

Yiddish is essentially a blend of medieval German (about 75%), Hebrew (20%), and bits of Slavic, Lithuanian, Hungarian, or Romanian, depending on where the speaker lived. A century ago, East European Jewish immigrants to the U.S. began adding English to the mix.

My grandmother, who did not speak English, would casually ask me to "open der vinder," failing to realize that she had absorbed at least some of the language of her new homeland. Even before the Nazi era, however, most Jews living in Germany and Austria disdained Yiddish and spoke genuine German.

Ashkenazi Jews mistakenly tend to lump all other Jews as Sephardic. (Sepherad is the ancient Hebrew name for the Iberian peninsula.) Sephardic people are descended from the Jews expelled from Spain and Portugal in the 15th and 16th centuries. They settled primarily in the lands bordering the Mediterranean Sea.

Their language is Ladino, which is largely medieval Spanish with touches of Hebrew and the languages of the countries in which they settled--e.g.., Turkish, Greek, Bosnian, or Arabic. Their new homelands, particularly in north Africa, Italy and Greece, contained tiny ancient Jewish communities (the last two called Romaniot), existing before their arrival. These people spoke Judeo-Arabic, Judeo-Italian, and Judeo-Greek. But in most cases they were absorbed into the larger Sephardic community.

In Israel there is increasing recognition of what are now regarded as Mizrahi or Eastern Jews. These are the Jews from Iraq, Yemen, Iran, Kurdistan, Georgia, Azerbaijan, and Uzbekistan (where they are known as Bukharan Jews). They speak Judeo-Persian, Judeo-Arabic, and other local languages that mix the native tongues with bits of Hebrew.

The Ashkenazi tendency to include these people as Sephardic has some legitimacy. Some Jews fleeing the Spanish Inquisition settled in these Asian lands, introducing their distinctive religious liturgy into local synagogues.

Aside from a common religion, what binds the Ashkenazi, Sephardic and Mizrahi Jews is Hebrew, the language of the Torah, used universally by all Jews for religious worship. Moreover, all the Jewish languages use the same written Hebrew alphabet.

As a boy in the Bronx, studying Spanish in high school, I recall picking up a newspaper printed in the Hebrew script in the local shoe repair shop owned by a Sephardic Jew from Turkey.

I was stunned to read what sounded to me as Spanish. It was a Ladino newspaper. The shoemaker said he was similarly surprised to encounter the sound of German when he tried to read a Yiddish newspaper.

When Israel was established, Hebrew was adopted as the new nation's official language, and the use of the other Jewish languages was discouraged.

On my first visit to Israel, I recall being emotionally moved to hear Hebrew, a language I had always associated only with old men praying in a synagogue, spoken by young people in the street and seeing its alphabet on the street signs and even on Army tanks.

Among the Ashkenazi Jews there has long been a kind of silly tribal rivalry between so-called "Litvaks" and "Galitziyaners," each claiming cultural superiority over the other, while apparently failing to acknowledge that they were other Yiddish-speaking Jews.

Litvaks are Jews who came from Lithuania, northeastern Poland and what is now Belarus. Galitziyaners, who enjoyed more tolerable treatment as citizens of the old Austro-Hungarian empire than the Litvaks did under Czarist Russia, came from what is now southern Poland and western Ukraine. Overshadowed by the Litvak-Galitiziyaner rivalry were other Yiddish-speaking Ashkenzi Jewish communities in what is now central Poland, the Czech Republic, Slovakia, Hungary, Rumania, and Moldova (formerly Bessarabia and Bukavina).

The complexity of European Jewish communal identity is underscored by the fact that Jews from Poland could be Litvak (if they came from the northeastern part of the country), Galitziyaner (if they came from the south), and neither if they came--like my father's family--from central Poland. The last group called themselves "Paylisheh Yidn," or simply Polish Jews.

This attempt to explain the Jews' complex cultural background deliberately omits any reference to their significant religious differences. That's an even more complicated issue requiring more space than this article can absorb and more patience than I possess.