The Z train uses skip-stop operation with the J train during weekday rush hours.
The J and Z share the Jamaica Line between Jamaica Center–Parsons/Archer in Queens and Manhattan. Under skip-stop service, some stations are served by the J and others by the Z, allowing selected trains to move more quickly during the busiest periods. Both services make all stops on portions of their routes outside the skip-stop section.
The Z is colored brown on subway maps because it uses the BMT Jamaica Line. It generally operates in the peak direction, while the J provides the more frequent all-day service.
Skip-stop service is sometimes misunderstood as meaning that the Z permanently bypasses the same stations every day. The exact service pattern depends on direction and time, and the Z does not run as a separate full-time route throughout the day.