A Boxer engine is a type of internal combustion engine where the cylinders are arranged horizontally in two opposing rows. This design allows for a lower center of gravity, which can improve vehicle stability and handling. The pistons move in and out in a horizontal motion, creating a unique engine sound and reducing vibrations. Boxer engines are commonly found in vehicles produced by Subaru and Porsche. Their compact design makes them suitable for sports cars and all-wheel-drive vehicles. The engine's layout also allows for more efficient airflow, contributing to better performance and fuel efficiency.