The Halakah is formally consists of the "mitzvoth" or commandments, that are directly derived from the teachings of the Torah, studious analysis of the text and possible meanings, and through the expositions formulated by rabbinical discussions through the early history of Judaism of which the Talmud is comprised
There are officially 613 mitzvoth that are clearly established in Judaism. This number is often a source of debate, but a definitive listing is only a matter of scholarship as some mitzvoth are overlapping, such as the two which respectively command that a Jew not work and must rest on the Shabbat. Of these, 365 of the mitzvoth (one for each day) are negative, specifically denying portions of reality from proper Jewish life, such as the common restrictions on the consumption of shellfish and pork, to the inability to accept ransom for a murder, which is specifically outlined in the mitzvoth. The remaining 248 mitzvoth, one for every bone in the male body, are affirmative, and actively describe acts and rituals which a Jew must follow. Also, as this is a code that has survived the testing of the millennia, some have become outlawed and inapplicable as the times have changed. Currently, there are approximately 270 mitzvoth that can be actively practiced by Jews living outside of the state of Israel, .
Also contained in the Jewish halakhah is the "gezeirah" or rabbinical law designed to prevent accidental violations of the mitzvoth. These are codes that were instituted by the early leaders of Jewish thought in order to strengthen the mitzvoth. For example, a dietary mitzvoth is one that forbids the boiling of meat with milk. This has been extrapolated into the form of a severe kosher dietary restriction, which prohibits even the cooking of the two in the same kitchen at the same time, so as not to allow the possibility of disobeying the mitzvoth. There is only a slight difference in the two, that while the mitzvoth is the unalterable code of law, a rabbi may waive or abate it if necessary.