Answer:
   
   There are at least two totally distinct meanings of the word Jew.
   
   The one that is germane to most of the issues of SCJ is what might
   best be described as a "member of the Jewish people." The people who
   are generally considered to belong to this group are enumerated under
   the heading "Who is a Jew", below.
   
   Although membership in "Am Yisrael," as we call the Jewish people, is
   determined by religious criteria, these criteria do not include the
   actual practice of Judaism. So Am Yisrael is truly a group of people
   who identify themselves as such, and not just a religion. Some people
   refer to Am Yisrael as a nation.
   
   Because many people have joined Am Yisrael through conversion over the
   years, Jews are not, at this point, a single ethnic group, any more
   than the French people. There are Jews of several different
   ethnicities, as described elsewhere in this FAQ.
   
   Nevertheless, there is an group that, for better or worse, is often
   described as Jews: the descendants of the ancient Hebrews, many of
   whom were dispersed across much of the earth during Roman times. And
   the vast majority of Am Yisrael belong to this group. To avoid
   confusion, we shall refer to this group as "descendants of the ancient
   Hebrews."
   
   It is sometimes unclear whether a frequently asked question about Jews
   refers to Am Yisrael or to the descendants of the ancient Hebrews. We
   shall give separate answers in case of confusion.
   
   In soc.culture.jewish, speaking as a Jew has the implication that one
   is currently Jewish, and not practicing another religion. Hence, a
   person born Jewish but practicing Islam should not write "I'm a Jew
   who accepts Muhammad's prophecy" but rather the more truthful "I'm a
   practicing Muslim of Jewish ancestry." Of course, Jews who practice
   other religions are welcomed and encouraged to return to practicing
   Judaism at any time.