A single-cylinder engine is a type of internal combustion engine that has only one cylinder. This design allows for a simpler and lighter engine, making it ideal for small vehicles like motorcycles and lawnmowers. The single cylinder contains a piston that moves up and down, creating the power needed to drive the vehicle. Single-cylinder engines are known for their efficiency and ease of maintenance. They typically produce less power than multi-cylinder engines but are often more fuel-efficient. This makes them a popular choice for applications where weight and simplicity are important, such as in small engines and portable equipment.