Jurisdiction generally describes any authority over a certain area or certain persons. In the law, jurisdiction sometimes refers to a particular geographic area containing a defined legal authority. For example, the federal government is a jurisdiction unto itself. Its power spans the entire United States.
Jurisprudence or legal theory is the theoretical study of law. Scholars of jurisprudence seek to explain the nature of law in its most general form and provide a deeper understanding of legal reasoning, legal systems, legal institutions, and the role of law in society.