The difference between civil law and common law systems lies in their sources and application of law. Civil law is based on comprehensive statutes and codes, with judges primarily applying written laws to cases. This system emphasizes legal predictability and uniformity. In contrast, common law relies on judicial precedents established by court decisions, allowing for greater flexibility and adaptability in legal interpretations. Judges in common law systems play a more active role in interpreting the law, using precedent as a guide while still considering the specifics of each case.