International commercial (trade) law is a set of legal norms of international and national law that regulate the relationships that arise in the conduct of a variety of trading activities. The UNIDROIT principles represent a completely new approach to the law of international trade because they are not an international convention subject to ratification by signatory states.
This is a set of international trade customs, “lex mercatoria,” collected and unified. The principles represent an autonomous legal order formed voluntarily by the parties participating in international economic relations and existing independently of national legal systems.
PECL is a set of model rules developed by leading contract law scholars in Europe. It attempts to change the basic rules of contract law and, more generally, the law of obligations common to most legal systems of European Union member states. The main purpose of the CISG is to develop a single law to alleviate the concerns of companies about the issues that may arise due to the fact that sellers and buyers use different local laws and regulations in the international sale of goods.
It can be said that the CISG is one of the main initiatives that serve the purpose of unifying extensive commercial law at the international level. The adoption of the CISG by countries has basically helped small businesses to open more legally to international markets, as it is challenging for small businesses to resolve contractual disputes with businesses located in another country.