Understanding legal terminology and abbreviations:

Legal Acronyms and Abbreviations - University of Washington, Gallagher Law Library

Glossary of Legal Terms - Oregon Judicial Department (see also

Nolo's Free Dictionary of Law Terms and Legal Definition

Prince's Bieber Dictionary of Legal Abbreviations

The Law Dictionary - Free online legal dictionary, featuring Black’s Law Dictionary, 2nd Ed.
 

Understanding legal citations:

Introduction to Basic Citations - Cornell University Law School's Legal Information Institute

How do I Cite Resources? - Univeristy of Chicago's D’Angelo Law Library

The Bluebook: A Uniform System of Citation