Orthodox Judaism is not a unified movement; rather it is composed of many different groups with intersecting beliefs, practices and theologies. In their broad patterns, the Orthodox movements are very similar in their observance and beliefs. However, they maintain significant social differences, and differences in understanding halakha due to their varying attitudes concerning (a) the role of women in Judaism, (b) relations with non-Orthodox Jews, (c) attitudes toward modern culture, and (d) how to relate to the modern State of Israel.
Since there is no one unifying Orthodox body, there is no one official statement of principles. Rather, each Orthodox group claims heir to the received tradition of Jewish theology, usually affirming a literal acceptance of Maimonides 13 principles as the only acceptable position. Some within Modern Orthodoxy take the more liberal position that these principles only represent one particular formulation of Jewish faith, and that others are possible.
Orthodox Jews view halakha (Jewish law) as a set of rules, and principles designed to create new rules, that were literally spoken to Moses on Mount Siani, and that were trasmitted with an incredibly high degree of accuracy. Creativity and development in Jewish law is held to have always been very limited; Orthodox Jews aver that when Jewish law has developed, it almost never took into account changing political, social or economic conditions.
Sephardic Orthodox Jews base their practices on the Shulkhan Arukh, the 16th century legal index written by Rabbi Joseph Karo; Ashkenazic Orthodox Jews base their practices on the Mappah, a commentary to the Shulkhan Arukh written by Rabbi Moses Isserles.
Orthodox Judaism maintains the traditional understanding of Jewish identity. A Jew is someone who was born to a Jewish mother, or who converts to Judaism in accordance with Jewish law and tradition. Orthodoxy thus rejects patrilineal descent. Similarly, Orthodoxy does not allow intermarriage. Intermarriage is seen as a deliberate rejection of Judaism, and an intermarried person is effectively cut off from most of the Orthodox community. However, some Chabad Lubavitch and Modern Orthodox Jews do reach out to intermarried Jews.
The following web page gives information about and/or direct links to over a dozen distinct Orthodox rabbinical bodies and movements: http://www.shamash.org/lists/scj-faq/HTML/faq/02-07.html
The role of women in Orthodox Judaism is discussed at this website: http://www.shamash.org/lists/scj-faq/HTML/faq/08-04.html
The Shulkhan Arukh: http://www.acs.ucalgary.ca/~elsegal/TalmudMap/ShA.html