England and Wales uses a common law system, and is where the system first originated. Other countries which operate under the common law system include the United States, Canada, Australia and New Zealand. However, the majority of countries in the world operate under civil law systems.
In common law systems, judges play a central role in interpreting and applying statute to cases. Where statute is silent or ambiguous, they can effectively create new law in the form of precedent. By contrast, judges in civil law systems are limited to applying the law as it already exists.