[From "Jewish Law"]
"I. THE CONCEPT OF HALAKHAH
Mishpat ivri is a part of the corpus of the Halakhah. Before defining mishpat ivri and discussing its nature, the meaning and content of the concept of Halakhah must be briefly examined.
The term Halakhah is used in a number of different senses. In its most general and usual sense, Halakhah refers to the normative portion of the Oral Law (Torah she-be-al peh). In this sense, Halakhah is used to contrast with Aggadah (or Haggadah), which denotes, inter alia, wise and ethical sayings, philosophical meditations, and admonitions. The Halakhah includes all of the precepts in Judaism--those laws involving the commandments concerning the relationship between people and God ('bein adam la-makom') as well as those laws applicable to relationships in human society ('bein adam le-havero').
The root of the word Halakhah is halokh ('to go'). As explained by Nathan b. Jehiel of Rome, the author of the Arukh: '[It is] something that proceeds [lit. 'goes and comes'] from beginning to end, or according to which Israel [i.e. the Jewish people] conducts itself [lit. 'the path in which Israel goes'].' Perhaps a clue to the correct philological explanation of the term Halakhah is furnished by a baraita that states:
'It was taught in the school of Elijah: Anyone who studies halakhot is assured of a place in the world to come, as Scripture says: 'His ways (halikhot) are everlasting.' Do not read it as 'His ways' (halikhot) but read 'His laws' (halakhot).'
The term halakhah was given additional meanings in Talmudic literature. (When used in this work in other than its general and usual sense, it is written with a small 'h.') Sometimes, halakhah designates 'the law' in the sense of a binding decision or ruling on a contested legal issue, as in the frequently used expression: 'The law (halakhah) is in accordance with the opinion of R. Judah.' Sometimes, halakhah refers not to the content of a particular precept but to its literary form. When a particular precept is stated as being derived form a verse in the Torah, it is called midrash; when it is presented on the basis of its own authority, in abstract form, it is called halakhah. The word halakhot (plural of halakhah) is also used to indicate a collection of a particular category of normative, or even non-normative, rules."