Final answer:
Cases generally begin in the trial courts, which are also known as district courts and are the lowest level of the federal judicial system. They handle both criminal and civil cases.
Step-by-step explanation:
In the United States, cases generally begin in the trial courts. These trial courts, also known as district courts, are the lowest level of the federal judicial system and handle both criminal and civil cases. They are responsible for hearing evidence, deciding guilt or liability, and determining appropriate penalties or damages.