A Jew is one who
a) was not born so and can no longer reproduce according to the first scientific principle of the Oral Torah because of past sexual activities, but supports the organization of infants and teenagers to maintain the scientific principles of the Oral Torah and reproduce offspring in line with the first principle of the Oral Torah. These are Generation Zero Jews (Gen-Zero Jews);
b) was born either by Gen-Zero Jews before they learnt about the Oral Torah, and was introduced to the scientific principles of the Oral Torah as infants or early teenagers (when they were still virgins). Therefore, they can be identified as Generation-Zero-plus Jews (Gen-Zero+ Jews) and they are different from Gen-Zero Jews because they can still reproduce in line with the first principle of the Oral Torah;
c) was born by Gen-O+ Jews. Thus, they are Generation-One Jews), or was born by Gen-One Jews (that means they are Gen-Two Jews), or was born by Gen-Two Jews (that is, they are Gen-Three Jews), and so on.
Learn more about the scientific principles of the Oral Torah [here].