Legal proceedings in civil-law and common-law systems have key differences to one another.
Inquisitorial
The judge(s) play an active role in proceedings and will question defence, prosecution and witnesses. The judge supervises the gathering of evidence to resolve the case and is in charge of the police investigation. The lawyers will pay close attention to the judge and can request that he or she considers particular evidence or follows a particular course of action, but ultimately the judge will decide which lines to follow.
This system is common in civil law jurisdictions such as Europe and South America.
Adversarial
The judge or jury knows nothing of the litigation until the cases have been presented in court. The parties are pitted against each other in the belief that the competition will lead to the truth. The parties present their cases to the decision makers such as judge or jury. When there is a jury, the judge is an impartial referee who advises the jury on matters of law.
The adversarial system is used in numerous countries such as Great Britain and The US. https://bit.ly/2VxsoKX