Civil law is a legal system originating in mainland Europe and adopted in much of the world. The civil law system is intellectualized within the framework of Roman law, and with core principles codified into a referable system, which serves as the primary source of law. The civil law system is often contrasted with the common law system, which originated in medieval England. Whereas the civil law takes the form of legal codes, the law in common law systems historically came from uncodified case law that arose as a result of judicial decisions, recognising prior court decisions as legally-binding precedent.

Historically, a civil law is the group of legal ideas and systems ultimately derived from the Corpus Juris Civilis, but heavily overlain by Napoleonic, Germanic, canonical, feudal, and local practices, as well as doctrinal strains such as natural law, codification, and legal positivism.

Conceptually, civil law proceeds from abstractions, formulates general principles, and distinguishes substantive rules from procedural rules. It holds case law secondary and subordinate to statutory law. Civil law is often paired with the inquisitorial system, but the terms are not synonymous. There are key differences between a statute and a code. The most pronounced features of civil systems are their legal codes, with concise and broadly applicable texts that typically avoid factually specific scenarios. The short articles in a civil law code deal in generalities and stand in contrast with ordinary statutes, which are often very long and very detailed.