They're citizenships, not nationalities.
Israel does this almost unique thing in the World which is split Citizenship from Nationality, with those who have the former only having the latter if they're Jews (constitutionally only a Jew can be an Israeli national). Further Israeli Citizenship is broken into Jewish Israeli and Non-Jewish Israeli, with the latter having less rights than the former (for example, Non-Jewish Israeli Citizens require "authorization" from local authorities to go live in certain parts of the country).
Israel was set up as an Apartheid state from the very beginning.
That said the other poster made a mistake: Palestinians are not Israelis - not even Non-Jewish Israeli Citizens - and have no rights at all in Israel. Further, there is no right to Israeli Citizenship by being born in Israel (unless you're a Jew: any Jew, anywhere in the World, has a right to Israeli Nationality, which also gives them Jewish Israeli Citizenship).
This has interesting effects such as people whose families have lived in Jerusalem for generations not having Israeli Citizenship because it was denied to them even though they were born there and lived there their whole lives. Of course, all of these people are not Jewish as all Jews constitutionally have a right to Israeli Nationality.
So By Law Israel has 3 different classes of people living there, in decreasing order of the rights they have:
- Jews, which by law are all Israeli Nationals (a Jew can literally arrive in Tel-Aviv, ask for Israeli Nationality and get it) and hence are also Jewish Israeli Citizens.
- Non-Jewish Israeli Citizens
- Non-Israeli Citizen, which includes all Palestinians even those born in the territory of Israel as Israel can and frequently does simply refuse to give them even just Non-Jewish Israeli Citizenship.
