A petrol engine is a type of internal combustion engine that operates using gasoline as its main fuel source. Synonyms for the term "petrol engine" include gasoline engine, motor engine, combustion engine, and spark-ignition engine. Given that there are different types of engines that are fueled by different sources, such as diesel engines that run on diesel fuel, the term "petrol engine" is used to specifically refer to engines that run on gasoline. Whether referred to as a petrol engine or any of its synonyms, these engines are widely used in vehicles, power generators, and other machinery that require the energy produced by combustion to function.