Appellate courts are specialized judicial bodies that review decisions made by lower courts, such as trial courts. Their primary function is to determine whether legal errors occurred during the trial that could have affected the outcome. Appellate courts do not conduct new trials or hear new evidence; instead, they focus on the application of the law and the procedures followed in the original case. These courts typically consist of a panel of judges who examine written briefs submitted by both parties, along with the trial record. The decisions made by appellate courts can lead to affirming, reversing, or remanding cases back to lower courts for further proceedings. In the United States, the highest appellate court is the Supreme Court.