The J.D. degree is the basic law degree. With a J.D. (and after passing a state Bar exam), you can be a lawyer, whether that involves practicing law, or working in business, or politics, or public service, or whatever you want.
The Law School's required courses, like Torts, Contracts, Property, and others, give you a solid foundation in law and the legal system. After that, the elective curriculum will let you build on that foundation by selecting courses from a wide range of legal specializations.