The OBD-II port is a standardized diagnostic interface found in most vehicles manufactured after 1996. It allows mechanics and vehicle owners to connect diagnostic tools to access information about the car's performance and identify issues. The port is typically located under the dashboard near the driver's seat. Using the OBD-II system, technicians can read trouble codes that indicate specific problems, monitor real-time data, and perform emissions testing. This helps ensure that vehicles run efficiently and meet environmental regulations. The OBD-II port is essential for maintaining vehicle health and facilitating repairs.