This definition refers to comparative law as a branch of law, but as was stated earlier comparative law is not a branch of law and is not only the study of legal institutions, it is the application of the comparative method to perform also comparative studies of legislation, case law, the enforceable law or custom. Alberto Justo For the process of discovering and examining the similarities and differences between two or more systems of law is called comparative law. This is a fairly broad definition of comparative law, but makes reference to only comparable legal systems it is not right for you can also compare part of legal systems, and when determining the similarities and differences is also important to determine the causes of such differences and similarities. For Enrique Martinez Paz comparative law is the discipline that aims, through analytical research, criticism and comparison of existing laws, to discover the fundamental principles and legal institutions to coordinate and present a positive system. To this author refers to comparative law as a discipline, however, the right not only investigates the laws, however, refers to seek to discover the fundamental principles and purpose of legal institutions and references that seeks to coordinate in Current positive system. To Edouard Lambert comparative law is not a science, but an art, or rather a technique with whose assistance, and by comparing different laws, “must be sought from the pool of legal institutions..