An overhead camshaft (OHC) is a type of engine design where the camshaft is located above the engine's cylinders. This setup allows for more direct control of the engine's valves, improving efficiency and performance. OHC engines can have one or two camshafts per cylinder head, known as single overhead camshaft (SOHC) and double overhead camshaft (DOHC) configurations, respectively. The primary advantage of OHC systems is their ability to allow for higher engine speeds and better airflow, which can enhance power output. This design is commonly found in modern vehicles, including many models from Toyota, Honda, and Ford.