Ship fuel, also known as marine fuel, is the type of fuel used to power ships and other vessels. The most common types are bunker fuel, which is a thick, heavy oil, and marine diesel, a lighter fuel used in smaller ships. These fuels are essential for the operation of engines that propel ships across oceans and waterways. The choice of ship fuel can impact both performance and environmental regulations. Low-sulfur fuel is increasingly being used to reduce harmful emissions, as many countries have implemented stricter rules to protect marine ecosystems. The shipping industry is also exploring alternative fuels, such as liquefied natural gas (LNG) and biofuels, to promote sustainability.