What is Trial Court?

Legal Definition
A trial court or court of first instance is a court having original jurisdiction, in which trials takes place.
-- Wikipedia
Legal Definition
A court of original jurisdiction where evidence and testimony are first introduced, received, and considered. Findings of fact and law are made in the trial court, and the findings of law may be appealed to a higher court that has the power of review.

A trial court of general jurisdiction may hear any civil or criminal case that is not already exclusively within the jurisdiction of another court. Examples include the United States district courts on the federal level and state-level trial courts such as the New York Supreme Courts and the California Superior Courts.

A trial court of limited jurisdiction may only hear specific kinds of cases based on subject matter, amount in controversy, statutory grant, or administrative matters.
Legal Definition
the court that will determine the facts and the laws in a certain case.